ISSN 1726-5274

Prevention and control

of microbiological hazards
in fresh fruits and vegetables –
Part 3: Sprout
Meeting report

43
MICROBIOLOGICAL RISK
ASSESSMENT SERIES
 43
MICROBIOLOGICAL RISK
ASSESSMENT SERIES

Prevention and control

of microbiological hazards
in fresh fruits and vegetables –
Part 3: Sprout
Meeting report

Food and Agriculture Organization of the United Nations

World Health Organization
Rome, 2023 i
Required citation:
FAO & WHO. 2023. Prevention and control of microbiological hazards in fresh fruits and vegetables –
Part 3: Sprout. Meeting report. Microbiological Risk Assessment Series No. 43. Rome, FAO. https://doi.
org/10.4060/cc3810en
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Contents
Acknowledgements vi
Contributors vii
Declaration of interests ix
Abbreviations and acronyms x
Executive summary xi

1 Introduction 1
1.1 Background 1
1.2 Objectives 2
1.3 Scope 3
1.4 Definitions 4

2 Overview of sprout production and supply chain 5

2.1 Seed production 5
2.1.1 Field preparation/planting 5
2.1.2 Growth 6
2.1.3 Seed harvest 7
2.1.4 Seed conditioning 7
2.1.5 Seed storage and distribution 7
2.2 Sprout production 8
2.2.1 Seed receipt 8
2.2.2 Seed storage 9
2.2.3 Seed treatment and pre-germination soak 9
2.2.4 Germination and growth 9
2.2.5 Harvest 10
2.2.6 Packaging 10
2.2.7 Storage and distribution 11

3 Microbiological hazards in sprouts 13

3.1 Outbreak/surveillance data 13
3.2 Pathogens of concern 13
3.3 Source and route of contamination 14

iii
 4 Prevention and control measures for seed production
and handling 15
4.1 Seed production 15
4.1.1 Animal and human activities 16
4.1.2 Manure, biosolids and other natural fertilizers 17
4.1.3 Agricultural water 18
4.1.4 Equipment associated with growing and harvesting 18
4.1.5 Tracking the source of contamination 18
4.2 Seed handling (processing and conditioning) 19
4.3 Storage and transport 20
4.4 Seed treatment (by seed suppliers) 20
4.5 Microbiological testing of seed (at the farm or by the seed supplier) 21

5 Prevention and control measures for sprout production 23

5.1 Water 23
5.2 Workers 24
5.5.1 Worker health and hygiene 25
5.5.2 Facilities 26
5.3 Production environment 26
5.4 Soil/growth media 27
5.5 Seed 28
5.6 Microbial testing 31
5.6.1 Target for testing and sampling plan 31
5.6.2 Testing laboratories 33
5.6.3 Test methods 34
5.6.4 Corrective actions 35
5.7 Post-harvest storage 35

6 Prevention and control measures during distribution

and at point-of-sale 37
6.1 Mitigation/intervention measures 38
6.2 Available data 39
6.3 Uncertainty and data gaps 40

iv
7 Records and traceability 41
7.1 Mitigation/intervention measures 42
7.2 Uncertainty and data gaps 44

8 Training 45

References 47

ANNEXES
Annex 1 Response to the Codex Committee on Food Hygiene (CCFH)
regarding specific interventions for sprouts 61
References 64
Annex 2 Sprout-associated foodborne illness outbreaks and surveillance
data 65
References 72

FIGURES
1. Typical seed production process 6
2. Typical sprout production process 8

v
 Acknowledgements
The Food and Agriculture Organization of the United Nations (FAO) and the
World Health Organization (WHO) would like to express their appreciation to all
those who contributed to the preparation of this report through the provision of
their time and expertise, data and other relevant information at all times before,
during and after the meeting. Special appreciation is extended to all the members
of the Expert Panel for their dedication to this project and to Dr Tong-Jen Fu for
her expert chairing of the Panel, and to Dr Lawrence Goodridge for his excellent
support as Rapporteur. All contributors are listed in the following pages.
The preparatory work and the expert meeting convened to prepare this report
were coordinated by the Secretariat of the Joint FAO/WHO Expert Meetings on
Microbiological Risk Assessment (JEMRA).

vi
Contributors
EXPERTS
Ana Allende, CEBAS-CSIC (Spanish National Research Council), Spain
Basharat Nabi Dar, Department of Food Technology, Islamic University of Science
and Technology, India
Tong-Jen Fu, Division of Food Processing Science and Technology, Center for
Food Safety and Applied Nutrition, Food and Drug Administration, the United
States of America
Lawrence Goodridge, Canadian Research Institute for Food Safety, University of
Guelph, Canada
Deon Mahoney, Produce Marketing Association Australia-New Zealand Ltd.,
Australia

RESOURCE PERSONS
Gro Skøien Johannessen, Section for Food Safety and Animal Health Research,
Norwegian Veterinary Institute, Norway
Jenny Scott, Office of Food Safety, Center for Food Safety and Applied Nutrition,
Food and Drug Administration, the United States of America

SECRETARIAT
Michelle D. Danyluk, Department of Food Science and Human Nutrition, Citrus
Research and Education Center (CREC), University of Florida, the United States
of America
Haruka Igarashi, Department of Nutrition and Food Safety, World Health
Organization, Switzerland
Christine Kopko, Food Systems and Food Safety, Food and Agriculture
Organization of the United Nations, Italy
Jeffrey LeJeune, Food Systems and Food Safety, Food and Agriculture Organization
of the United Nations, Italy

vii
 Moez Sanaa, Department of Nutrition and Food Safety, World Health Organization,
Switzerland
Kang Zhou, Food Systems and Food Safety, Food and Agriculture Organization of
the United Nations, Italy

viii
Declaration of interests
All participants completed a Declaration of Interests form in advance of the
meeting. The interests declared were not considered by FAO and WHO to present
any conflict in light of the objectives of the meeting.
All the declarations, together with any updates, were made known and available
to all the participants at the beginning of the meeting. All the experts participated
in their individual capacities and not as representatives of their countries,
governments or organizations.

ix
 Abbreviations and acronyms
CAC Codex Alimentarius Commission
CCFH Codex Committee on Food Hygiene
CCPs critical control points
CFIA Canadian Food Inspection Agency
EFSA European Food Safety Authority
FAO Food and Agriculture Organization of the United Nations
FDA United States Food and Drug Administration
GAPs good agricultural practices
GHPs good hygiene practices
HACCP hazard analysis and critical control point
JEMRA Joint FAO/WHO Expert Meetings on Microbiological Risk Assessment
LMICs low- and middle-income countries
RTE ready-to-eat
STEC Shiga toxin-producing Escherichia coli
WHO World Health Organization

x
Executive summary

BACKGROUND AND OBJECTIVE

In 2019, following a request from the Codex Committee on Food Hygiene (CCFH),
the Codex Alimentarius Committee (CAC) approved new work at its 42nd
Session on the development of guidelines for the control of Shiga toxin-producing
Escherichia coli (STEC) in leafy vegetables and in sprouts (FAO and WHO, 2018).
To support the work of the CCFH and to update and expand the information
available in “Microbiological Hazards in Fresh Leafy Vegetables and Herbs”
(MRA14, FAO and WHO, 2008), FAO and WHO are convening a series of expert
meetings on preventing and controlling microbiological hazards in fresh fruits and
vegetables.
In September 2021, the Joint FAO/WHO Expert Meetings on Microbiological Risk
Assessment (JEMRA) meeting on the Prevention and Control of Microbiological
Hazards in Fresh Fruits and Vegetables reviewed relevant measures for the control
of microbiological hazards from primary production to point-of-sale in fresh,
ready-to-eat (RTE) and minimally processed fruits and vegetables, including leafy
vegetables (FAO and WHO, 2021b).
A sprout expert meeting was held in November 2021 that reconvened a subset of
the JEMRA Expert Committee to collect, review and discuss relevant measures for
the control of microbiological hazards in sprouts, from the production of seed for
sprouting, to the harvesting and packing of sprouts and to point-of-sale.
A final meeting on the Prevention and Control of Microbiological Hazards in Fresh
Fruits and Vegetables to collect, review and discuss relevant commodity-specific
interventions for all other fresh fruits and vegetables from primary production to
point-of-sale was held in July 2022.

SCOPE
Sprouts have different food safety concerns from other fresh fruits and vegetables
because the conditions under which sprouts are produced (time, temperature,
humidity, pH and nutrients) are ideal for foodborne pathogen growth. Outbreak
investigations have demonstrated that foodborne pathogens found on sprouts
most likely originate from the seed, but the contamination could also be attributed
to the production environment.

xi
 This report covers prevention and control measures specific to the primary
production and handling of seed for sprouting, the production of sprouts and
hygienic practices applicable to retail and food services. Recommendations for
proper record-keeping and the establishment of product traceability programmes
that facilitate the identification and investigation of contaminated seed and sprouts
in the event of an illness outbreak or product recall are also included.
Microbiological hazards and control measures related to shoots, cress and
microgreens where the growth stage is longer and the seeds or roots are not kept
in the final product are not covered in this report. Home sprouting or consumer
interventions (e.g. cooking) are not covered either.

MICROBIOLOGICAL HAZARDS IN SPROUTS

Sprouts represent a unique food safety challenge because the proliferation of
bacterial pathogens, if present, is enhanced due to the high humidity and the ideal
sprouting temperature. For this reason, the Expert Committee identified foodborne
bacterial pathogens of concern, including Shiga toxin-producing Escherichia coli
(STEC), Salmonella spp., and Listeria monocytogenes and specifically focused on
interventions against bacterial foodborne pathogens. While the seed for sprouting
may be contaminated with viral or parasitic pathogens, viruses and parasites do not
increase in numbers during sprout production and few viral or parasitic disease
outbreaks have been attributed to sprouts.

PREVENTION AND CONTROL MEASURES

FOR SEED PRODUCTION AND HANDLING
When outbreaks have been linked to sprouts, the seed for sprouting was typically
identified as the source of contamination. Seed can be produced for use as human
food and animal feed and is generally treated as a raw agricultural product.
Controlling and/or reducing microbial contamination of seed is difficult, given
the diversity of growing and harvesting practices associated with seed production.
Bacterial pathogens, if present on the seed, may survive for long periods of time
during seed storage. Additionally, there may be difficulties in the traceability of the
seed from harvest to sprouting. Nevertheless, interventions aimed at reducing the
risk from seed-borne contamination should focus on controlling contamination
from animal and human activities, ensuring proper use and application of manure,
biosolids, other natural fertilizers and using agricultural water that is fit for
purpose. Equipment used to grow, harvest and transport seed should be designed
to enable effective cleaning and sanitation, which should be conducted regularly.

xii
Measures should be taken during seed processing, conditioning, storage and
transportation to reduce the risk linked to microbial contamination due to
improper handling or exposure to extraneous material. Seed treatments represent
an approach to reducing microbial contamination.

• Animal and human activities

> Grazing of domestic animals should not occur in fields while crops are
actively being grown for seed production.
> Wild animals should be excluded from the production area to the extent
possible.
• Manure, biosolids and other natural fertilizers
> Manure, biosolids, and other natural fertilizers are potential sources
of bacterial pathogens.
> To reduce the risk linked to seed contamination, only adequately treated
or composted manure/biosolids should be utilized during seed production.
> In general, the time intervals between application of manure/compost/
biosolids and planting and harvest of seed should be maximized, as
bacterial pathogens die off over time. A pre-harvest interval of 60 days
from application is considered to be the minimum duration.
• Agricultural water
> Fit-for-purpose water for irrigation as well as other applications should be
used to avoid the introduction of pathogens into seed.
> The application method and timing of irrigation will also impact the risk.
• Equipment associated with growing and harvesting
> Equipment should be designed and maintained to minimize soil intake
and seed damage and to prevent the introduction of pathogens into seed.
> Equipment should be cleaned and sanitized prior to harvest.
• Seed handling
> Seed may become contaminated during harvesting, threshing and drying.
> Control of moisture content will decrease microbial growth and pathogen
viability.
• Storage and transport
> Seed can become contaminated during storage and transportation due to
unsanitary conditions or improper handling.
> Temperature and humidity should be controlled and appropriate

xiii
 hygiene conditions implemented, including the cleaning and sanitation
of equipment used to transport the seed.
> Animal and insect controls should be implemented.
• Seed treatment
> Treatment of seed to reduce the presence of pathogens is a potential
critical control point.
> Seed treatment can be challenging due to the low water activity of the
seed, and the need to preserve the viability of the seed and its ability to
germinate.
• Microbiological testing of seed
> The likelihood of detecting the presence of pathogens in seed is extremely
low, due to the heterogeneous distribution and low numbers of the
pathogens contaminating the seed.

PREVENTION AND CONTROL MEASURES

FOR SPROUT PRODUCTION
Preventive and control measures need to be put in place to avoid water, workers,
the production environment, growth media or seed from serving as the source
of contamination or as a vehicle for cross-contamination.
The production process should be based on a Hazard Analysis and Critical Control
Point (HACCP) system, where all the steps are well-documented and potential
critical control points (e.g. decontamination of the seed) can be identified and
controlled. If a problem is identified, a critical revision of all the steps should be
performed.

• Water
> Water needs to be fit-for-purpose.
> The microbiological quality of water used in production and processing
of sprouts should be maintained and monitored during the production
and/or processing day, particularly if the same water is used in contact
with large quantities of product.
• Workers
> Personal health and hygiene measures need to be implemented to avoid
workers becoming a vector of contamination for sprouts.

xiv
• Production environment
> Sprout producers must take measures to control contamination that
may arise from equipment, food and non-food contact surfaces, air and
stagnant water. Proper storage, handling and disposal of waste and effective
pest control will minimize the risks linked to sprout contamination.
> Proper facility design (e.g. differentiation between areas and zones) and
operation flow to prevent raw material from coming into contact with the
final product will reduce the risks linked to cross-contamination.
> Environmental monitoring is important to identify sources of
contamination, particularly for L. monocytogenes, which may become
established in the sprout production environment.
• Soil/growth media
> Natural fertilizers of animal origin need to be treated and handled so as to
minimize the risk of sprout contamination.
• Seed
> Seed should be sourced from producers or distributors that follow good
agricultural practices (GAPs) and good hygiene practices (GHPs) during
the production, storage, distribution and sale of the seed.
> When seed arrives at a sprout operation, it should be inspected for
physical damage and signs of contamination. Once received, it should
be stored and handled in a manner that will avoid damage, prevent
growth of microorganisms and protect it from pests and other sources
of contamination.
> Seed treatment:
> Due to the difficulty of obtaining seed that can be guaranteed
as pathogen free, the decontamination of seed prior to the sprouting
process is recommended to reduce the risk of foodborne illness.
> Many decontamination treatments are available, including physical
and chemical treatments. The effectiveness of treatments is highly
variable between published studies and has rarely been validated
under industrial conditions, which is a limitation for the extrapolation
of results to industrial applications.
• Microbial testing
> Microbial testing can be done at many different stages of the sprout
production. Spent sprout irrigation water has been identified as an
appropriate target for microbial testing.

xv
 > Microbial testing should be considered a verification that the seed used
for sprouting and the production process does not contribute to sprout
contamination. It will enable early detection of contaminated production
batches, thus preventing their entrance into the marketplace.

PREVENTION AND CONTROL MEASURES DURING

DISTRIBUTION AND POINT-OF-SALE

• Potential for bacterial growth and contamination can occur during transport,
distribution and at point-of-sale due to improper handling, poor personal
hygiene, contamination through commingling with raw commodities, animals
or animal products, and exposure to unsanitary surfaces or water.
• Mitigation strategies include the training of operators and retailers, the use
of clean, enclosed, refrigerated transport vehicles, a clean and sanitary point-
of-sale environment, and fit-for-purpose water for cleaning, sanitizing and
cooling.
• Sprouts should be kept at refrigeration temperature that will minimize
microbial growth for the intended shelf-life of the product. The temperature
of storage areas and transport vehicles should be monitored.
• For in-restaurant sprouting, interventions recommended for sprout operations
should be considered, including seed sourcing programmes, seed treatment
(if appropriate), the sampling and testing of spent sprout irrigation water
(samples to be tested by contract labs) as well as cleaning and sanitizing food
contact surfaces.

RECORDS AND TRACEABILITY

• Seed producers and suppliers should have a system to effectively identify seed
lots, trace their associated production sites and agricultural inputs and allow
for the physical retrieval of the seed in the event of a suspected hazard.
• Sprout operations should ensure that records and traceability programmes are
in place to effectively respond to health risk situations.

xvi
TRAINING

• All personnel involved in the production and handling of seed for sprouting
or sprouts across the supply chain should receive training on the principles
of food hygiene and food safety as well as personal health and hygiene
requirements.
• Seed producers, handlers, distributors and processors should be aware of GAPs
and GHPs and of their role and responsibility in protecting seed intended for
sprouting from contamination.
• Interventions designed to reduce microbiological hazards in sprouts can
be highly technical and difficult to implement. Specific training related to
seed sourcing and storage, seed treatment, sampling and microbial testing,
cleaning and sanitizing and record-keeping are required to ensure successful
implementation.
• It is important to develop a network of experts and technical support to enable
the dissemination of accurate and complete information on safe production
and handling of sprouts.

xvii
Introduction
1
1.1 BACKGROUND
Fresh fruits and vegetables are an important part of a healthy diet and are protective
against many chronic health conditions, yet fresh fruits and vegetables are
increasingly being implicated in food safety incidents involving microbiological
hazards around the globe. Fresh produce contaminated with foodborne pathogens
(e.g. bacteria, viruses, protozoa, helminths) has resulted in numerous outbreaks of
foodborne illness and trade disruptions.
The Codex Alimentarius Commission (CAC) initially developed the “Code of
Hygienic Practice for Fresh Fruits and Vegetables” in 2003, then later revised it
in 2010 following a JEMRA meeting, held in 2008, to address the microbiological
hazards associated with leafy vegetables and herbs (MRA14) (FAO and WHO, 2008).
In addition, several commodity specific annexes were added to the code
of practice in 2012, 2013, and 2017 (FAO and WHO, 2017).
Subsequently, in 2018, FAO and WHO published the report “Shiga toxin-
producing Escherichia coli (STEC) and food: attribution, characterization, and
monitoring” (MRA31), in which fresh fruits and vegetables were identified as
important sources of STEC infection (FAO and WHO, 2018). In 2019, following a
request from the Codex Committee on Food Hygiene (CCFH), the CAC approved
new work at its 42nd Session on the development of guidelines for the control
of STEC in leafy greens and in sprouts. More recently, in October 2020, a JEMRA
meeting on Listeria monocytogenes in ready-to-eat (RTE) foods noted increased
reports of listeriosis linked to fresh and minimally processed fruits and vegetables
(FAO and WHO, 2022).

1
 To meet the request of the CCFH and to update and expand the information
available in the previous report on “Microbiological Hazards in Fresh Leafy
Vegetables and Herbs” (MRA14), FAO and WHO held a series of JEMRA meetings
from July 2021 to June 2022 on preventing and controlling microbiological hazards
in fresh fruits and vegetables. The goal of these expert meetings was to gather
recent data, evidence and scientific opinions on the topic.

1.2 OBJECTIVES
The purpose of the JEMRA meeting on sprouts was to collect, review and discuss
relevant measures for the control of microbiological hazards in sprouts, from the
primary production of seed, to the growing of sprouts and to point-of-sale.
The scope of the meeting included aspects of seed production, processing and
procurement, sprout propagation (hydroponically, in substrate and soil) and
distribution, point-of-sale, record-keeping and traceability. Emphasis was placed
on the identification and evaluation of preventive measures to reduce foodborne
illnesses associated with sprouts, taking into consideration their effectiveness and
practicalities.
The regulatory expectations and limitations of individual countries were not the
focus of the meeting. It is understood that individual country regulations may not
align with the definitions or subsections, but it is expected that the information
presented will still be useful and can advance the understanding of hazards and
risk mitigation.
The objectives of the meeting included:

• identifying and characterizing the microbiological hazards associated with

sprouts, including pathogens of concern and potential sources/routes of
contamination;
• reviewing mitigation/intervention measures being used at different points
along the sprout supply chain and assessing their effectiveness in reducing
microbiological hazards;
• reviewing publicly available literature, guidelines from competent authorities
and industry associations (e.g. compliance guidelines, codes of practice) to
assess the current state of knowledge on controlling microbiological hazards
in sprouts; and
• responding to specific questions posed by the CCFH (Annex 1).

2 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
1.3 SCOPE
Reports of foodborne illness associated with raw and lightly cooked sprouts have
raised concerns among public health agencies and consumers about the safety
of these products.
Microbial pathogens associated with sprouts include Shiga toxin-producing
Escherichia coli (STEC), Salmonella spp., Listeria monocytogenes, and other
pathogens. Sprouts have different food safety concerns from other fresh
fruits and vegetables because the conditions that favour sprout production
(time, temperature, humidity, pH, and nutrients) are also ideal for foodborne
pathogen growth. Outbreak investigations have indicated that the foodborne
pathogens found on sprouts most likely originate from the seed, but the
contamination can also be attributed to the production environment.
Seed is commonly identified as the primary source of microbial contamination
in sprouts. Crops for seed production are grown in typical agricultural
environments and potential sources of contamination in the field include water,
improperly managed animal manure, contact with wild animals and inadequate
worker hygiene. The risk of sprout contamination can be reduced through the
implementation of preventive measures used on farms to avoid contamination
of seed. Good agricultural practices (GAPs) should be applied at all stages for seed
destined for sprout production, including planting, growing, harvesting, cleaning,
storage and transportation.
Poor hygienic practices and an insanitary production environment could also
lead to sprout contamination. Preventive and control measures should be in place
during sprout operations to prevent water, workers, production environment,
growth media or seed from serving as the source of contamination or as a vehicle
for cross-contamination.
Seed treatments represent one approach to reducing microbial contamination.
There is currently no treatment available that can guarantee pathogen-free seed.
Research is needed to find and validate effective decontamination treatments
that provide sufficient pathogen reduction without affecting the germination rate
of the seed.
Microbial testing can be performed at many stages of sprout production.
Testing will enable the early detection of contaminated production batches.
It is also a verification that seed used for sprouting and the production process
does not contribute to sprout contamination. This report covers prevention and
control measures specific to the primary production and handling of seed for
sprouting, the production of sprouts, and hygienic practices applicable to retail and

CHAPTER 1 – INTRODUCTION 3
 food services. Recommendations for proper record-keeping and the establishment
of product traceability programmes that facilitate the identification and
investigation of contaminated seed and sprouts in the event of foodborne illness
outbreak or product recall are also included.

1.4 DEFINITIONS
Cress – grown in substrate and true leaves are developed. The shoots and the leaves
are cut during harvest and the final product does not include the seed and roots.
Growth media – material that acts as a substrate during growth of the sprout.
Microgreens – plants reach a later stage of growth than sprouts, typically
associated with the emergence of true leaves. Can be grown in soil or substrate and
are harvested above the soil or substrate line. Include both shoots and cress.
Seed distributor – a person responsible for the distribution (handling, storage and
transportation) of seed to sprout producers and who may deal with one or more
seed producers or also be a seed producer.
Seed producer – a person responsible for the management of activities associated
with the primary production of seed, including post-harvest practices.
Shoots – grown hydroponically and true leaves are developed. The shoots and the
leaves are cut during harvest and the final product does not include the seed and
roots.
Spent sprout irrigation water – water that has been in contact with sprouts during
the sprouting process.
Sprouts – sprouted seed or beans harvested when the cotyledons (or seed leaves)
are still un- or under-developed and true leaves have not begun to emerge.
They can be grown in water, soil or substrate, and can be harvested with or without
the root (cut sprouts).
Sprout producer – a person responsible for the management of activities associated
with the production of sprouts.
Traceability – means the ability to trace and follow a food, feed, food-producing
animal or substance intended to be, or expected to be incorporated into food and
feed, through every stage of production, processing and distribution.

4 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
Overview of sprout production
2
and supply chain

2.1 SEED PRODUCTION

Seed for sprouting is mostly grown in agricultural environments. Specific
production practices vary depending on the type of crop and seed used.
Some crops are grown exclusively for seed while others are grown for both forage
and seed. Only a small proportion of harvested seed is used for sprouting. In many
cases, seed purchased by sprout producers is not usually grown specifically for this
purpose. Seed production generally consists of the steps shown in Figure 1.

2.1.1 Field preparation/planting

Practices to establish a highly productive seed crop include proper site selection,
removal of soil limitations with tillage and fertilization, good seeding technique
and timing, effective weed management, proper irrigation and proper timing of
harvest (Putnam et al., 2012).
The optimal growing environment differs between seed crops. Alfalfa seed production
favours deep, well-drained soils, heavier clay or loam soils over lighter, sandy soils
(Mueller, 2008). Mung bean production prefers sandy, loam soils with good internal
drainage. The field is tilled to remove weeds and to prepare a seedbed that will provide
good seed-soil contact. The soil should be smooth, firm and free from clods and
debris for optimal seed placement (Oplinger, 1990; Wells, Holen and Sheaffer, 2018).
Nutrients are essential for optimal crop growth and seed production. The amount
of fertilizer needed is determined by soil or tissue tests (NACMCF, 1999).

5
 FIGURE 1 Typical seed production process

Field preparation/planting

Growth

Seed harvest

Seed conditioning

Seed storage

Seed transport and distribution

Source: Authors’ elaboration for this report.

Planting can be done manually or mechanically using drills, seeders or other

planting equipment. For some seed types (e.g. broccoli), seeding is started in a
greenhouse or nursery bed, followed by transplantation after several weeks.

2.1.2 Growth
Properly timed agricultural practices are key to successful seed production. Seed
yield and quality can be impacted by factors such as pollination, irrigation, insects
and weed controls (NACMCF, 1999).
Pollination requirements for seed crops vary among different species and depend
on whether a plant is self-pollinating or requires cross-pollination to facilitate the
seed set. Insects (e.g. honeybees) are commonly used pollinators.
Irrigation is needed for field preparation, the promotion of the seed set and the
prevention of plant stress that may reduce seed yield. Most irrigation systems
are surface systems, e.g. flood, furrow or sprinkler irrigation. Timely irrigation
scheduling is essential. For alfalfa production, irrigation starts in the winter to
provide half of the water requirement for the year. Deciding when to stop irrigating
a field for the season is also important. It is a fine balance, as sufficient water is

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required for the seed to mature, but the moisture must be removed from the soil
prior to desiccation for harvest (NACMCF, 1999).
Insecticides must be carefully selected and applied to kill the target insects without
harming the bees required for pollination. Weed control will eliminate competition
and promote the growth of the seed crop. Mechanical cultivation and herbicides
are used to control weeds. In some regions, grazing sheep may be employed in
seedling fields to control the weeds (NACMCF, 1999).

2.1.3 Seed harvest

Seed harvest involves cutting (swathing), windrow curing and threshing.
For example, alfalfa seed is swathed after two-thirds or three-quarters of the pods
have changed from green to dark brown. After cutting, the plants are left in long
strips (or windrows) in the field. When seed is mature and adequately dry, it is
removed from the pods either by hand or by machine. Harvesting practices expose
the seed to dirt and debris and may cause damage to the seed. Harvested seed
should be cleaned quickly to remove stems, immature pods, dirt, insect parts and
other debris.

2.1.4 Seed conditioning

Seed conditioning eliminates soil, weed seeds and other debris by employing a
variety of equipment that separates the seed- and non-seed fractions based on
differences in physical characteristics, such as particle size, shape, density and
surface texture. Some legume seeds are difficult to germinate because they have
a hard seed coat that is less permeable to water. Mechanical scarification or
scratching the seed coat are sometimes applied to improve the germination of hard
seeds (NACMCF, 1999).
Seed conditioning, shipping and distribution practices often involve mixing
multiple lots of seed of different origins, which may complicate traceback and may
also present an opportunity for cross-contamination.

2.1.5 Seed storage and distribution

Seed is commonly warehoused in metal bins until it is bagged. Once bagged,
seed needs to be protected from rodents, insects, excess moisture and other
contaminants. Proper storage temperature, humidity and seed moisture content
are critical to maintain seed longevity and prevent bacteria or mould growth.

CHAPTER 2 – OVERVIEW OF SPROUT PRODUCTION AND SUPPLY CHAIN 7

 2.2 SPROUT PRODUCTION
Sprouts are typically grown in enclosed buildings or greenhouses. They can be
grown hydroponically or in soil. During sprout production, the seed is moistened
to increase the water content. The water used in sprouting operations is either
municipal water or ground water: in any case, water that comes into contact
with sprout seed or sprouts should not represent a vector of contamination.
The production process broadly follows the steps depicted in Figure 2. The specific
conditions (e.g. length of pre-germination soak, days of sprouting, irrigation
frequency, post-harvest wash, packaging) used may differ depending on the type
of seed being sprouted and the size and resources of the operation.

FIGURE 2 Typical sprout production process

Seed receipt Seed storage Pre-germination Rinse

soak

Germination Harvest Wash Drain

and growth

Cool Packaging Cooling Distribution

and storage

Source: Adapted from the National Advisory Committee on Microbiological Criteria for Foods (NACMCF, 1999).
NACMCF (National Advisory Committee on Microbiological Criteria for Foods). 1999. Microbiological safety
evaluations and recommendations on sprouted seeds. International Journal of Food Microbiology, 52(3):123
-153. https://doi.org/10.1016/ S0168-1605(99)00135-X

2.2.1 Seed receipt

Sprout producers source their seed globally. Established guidelines have recommended
that sprout producers only purchase seed that has been grown using good agricultural
practices (GAPs) and that is conditioned and stored under sanitary conditions
(EC, 2017/C 220/03; FDA, 2017a). The European Union has set regulations requiring
sprout producers to have procedures in place to ensure good hygienic production of
the seed and the traceability of the production seed lots (EC, 2017/C 220/03).
Seed is received at sprouting operations in bags or sacks (50 lb or 25 kg). The bags
are typically tagged with supplier information, seed type, lot code and country
of origin. Other documents that may accompany a shipment of seed are: certification
of analysis (specifications for purity or percent germination), microbiological
testing results and certification of pre-treatment if the seed has been previously
treated by the seed supplier.

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Bags and seed are inspected upon delivery for physical damage (e.g. holes, tears)
and signs of contamination (e.g. insect, bird or rodent droppings, foreign material).
Contaminated or potentially contaminated seed should not be used for sprouting.

2.2.2 Seed storage

The storage area for seed should be clean, dry and free of pests and should be
separate from areas that store packaging materials, chemicals or finished products.
The seed should be handled and stored in a manner that will prevent damage and
contamination (e.g. keeping seed away from walls and off the floor to prevent
rodent contamination) and facilitate inspection for signs of contamination.

2.2.3 Seed treatment and pre-germination soak

Many sprout producers apply an antimicrobial treatment to seed prior to sprouting
to reduce pathogenic microorganisms, if present. Treatment of seed for sprouting
is recommended by international guidelines (CFIA, 2008; FAO and WHO, 2017)
and is required in certain jurisdictions (e.g. the United States of America).
Both chemical (e.g. calcium hypochlorite) and physical (e.g. hot water dip) methods
are currently used in sprout operations (FDA, 2017c). The known seed treatment
methods based on chemical, physical or biological means or a combination of
these have been extensively reviewed (Ding, Fu and Smith, 2013; Sikin, Zoellner
and Rizvi, 2013; Yang et al., 2013). All the steps involved in the antimicrobial
treatment of seed should be carried out in an area separate from the germination
and packaging areas. After treatment, the seed is generally soaked for up to
12 hours in water to soften hulls and improve germination (NACMCF, 1999).

2.2.4 Germination and growth

Sprouts are grown hydroponically, in substrate or in soil. The practices employed
for germination, growth, harvest and post-harvest washing vary depending on the
operation and the type of sprout grown. Growing units range from rotating drums
to bins, beds, trays and buckets. Germination and growing times differ with the
type of sprout, the time of year and the germination process used. They can range
from 3 to 7 days for alfalfa, 3 to 8 days for mung bean, 6 to 10 days for onions
or 3 to 14 days for wheat grass, etc. (NACMCF, 1999).

2.2.4.1 Hydroponically grown sprouts

Green sprouts (e.g. alfalfa, broccoli, clover and radish) are commonly grown
in rotating drums. Drums are pre-set for rotation speed, water temperature
and air ventilation. The growing sprouts may receive a water spray every 10 to
15 minutes with air blown into the drum to keep the product ventilated.

CHAPTER 2 – OVERVIEW OF SPROUT PRODUCTION AND SUPPLY CHAIN 9

 Some sprout operations germinate the seed initially in rotary drums for 2 to 3 days
then transfer it to trays, cups or final packages for further growth. These containers
are placed on growing racks for 3 to 5 days. Via this process, sprouts will grow
vertically in a more uniform manner and turn greener in colour (NACMCF, 1999).
Mung bean sprouts are generally sprouted in large quantities (25 kg) in deep bins or
beds in dark and humid rooms with temperatures between 21 and 30 °C. Irrigation
water is typically applied via a moving overhead sprinkler system once every
4 to 6 hours (Hora et al., 2005; NACMCF, 1999).

2.2.4.2 Soil grown sprouts

Soil grown sprouts are commonly planted in plastic trays that contain potting soil or
composted soil. The seed is rinsed, then soaked in water and held for 12 to 24 hours
to allow for initial germination. The soaked seed is then scattered on top of the soil
and levelled out. Water is sprayed over the trays once or twice daily (NACMCF, 1999;
SproutPeople, 2022).

2.2.5 Harvest
Sprouts are typically harvested by manually removing them from growing units.
Some sprout operations wash sprouts in a water bath or in a flume system to
remove hulls and/or to help lower the temperature of the sprouts. After washing,
excess water is removed using a centrifuge. Most soil-grown sprouts are harvested
at the facility, by cutting them from the trays, and then washed and packaged.
Alternatively, the sprout trays are delivered directly to retailers (e.g. juice bars)
where sprouts are cut at the point-of-sale. Sprouts are often placed in a cold room
or a cooler after harvest to remove the heat generated during the sprouting process
before packaging (FDA, 2017a).

2.2.6 Packaging
Sprouts are typically packaged at the growing site, but in some cases, they are
transported in bulk to another location to be packaged. Sprouts are commonly
packaged in large (e.g. 10 lb) bulk or small (e.g. 4 oz) individual containers
for delivery to restaurants or retail markets. Types of packaging used include
plastic bags, plastic cups or box-type containers, clam shells and soil trays
(NACMCF, 1999).

2.2.7 Storage and distribution

After packaging, sprouts are stored in cold rooms or coolers. Because the sprouts are
still respiring, they can generate heat. Rapid cooling is preferred to stop sprout growth
and to increase shelf-life. It is important to provide good air circulation for cooling.

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The cold chain should be maintained throughout distribution of the finished
products. Sprouts are shipped in refrigerated vehicles or with added ice if using
trucks with no refrigeration. It is important to maintain the cold chain when
preparing the products for loading onto delivery trucks.
Certain jurisdictions have set requirements for the temperature of sprouts received
at retail. For example, in the United States of America, sprouts are classified
as a “TCS” (Temperature Control for Safety) food and must be maintained
at a temperature at or below 5 °C upon arrival at the point-of-sale.

CHAPTER 2 – OVERVIEW OF SPROUT PRODUCTION AND SUPPLY CHAIN 11

Microbiological hazards
3
in sprouts

3.1 OUTBREAK/SURVEILLANCE DATA

The presence of robust food safety surveillance systems in high-income countries
(HICs) enables effective traceback and the epidemiological studies required for
source attribution and the identification of foodborne illness outbreaks in which
sprouts were the identified vehicle. The lack of such surveillance systems in
low- and middle-income countries (LMICs) means that the prevalence of microbial
contamination in sprouts or the sources of foodborne illness outbreaks are often
not identified. Examples of bacterial contamination rates and prevalence in sprouts
sampled from the marketplace and a summary of foodborne illness outbreaks
associated with sprouts are provided in Annex 2. The lack of identified sprout-borne
outbreaks from LMICs reflects the paucity of data from these countries.

3.2 PATHOGENS OF CONCERN

Sprouts represent a unique food safety challenge because the conditions under which
sprouts are produced are ideal for the growth of bacterial foodborne pathogens.
For this reason, this document identifies pathogens of concern as bacterial
foodborne pathogens, including STEC, Salmonella spp. and L. monocytogenes,
among others, and it specifically focuses on interventions for bacterial foodborne
pathogens. While the seed may be contaminated with viral or parasitic pathogens,
they do not grow during sprout production. Nevertheless, the presence of viral and
parasitic pathogens on sprouts may represent a hazard, should they be present.

13
 3.3 SOURCE AND ROUTE OF CONTAMINATION
The microbial contamination of sprouts is often attributed to the seed
(Bazaco et al., 2021; Dechet et al., 2014). Much focus has been placed on the safe
production, conditioning, storage and transportation of seed for sprouting to
prevent seed contamination. Agricultural practices vary between seed produced
for the production of sprouts for human consumption and seed planted for
animal feed.
If seed intended for forage, animal grazing or other uses is used for sprouting,
sprout producers should be aware of the potential contamination of seed from
natural fertilizers or irrigation water. To avoid potential microbial risks, only seed
produced using adequate GAPs should be used for the production of sprouts.
Under the conditions in which seed is sprouted (time, temperature, humidity, pH,
and nutrients), if low levels of microbial contaminants are present on the seed, they
can grow to reach high levels. Little information is available for comparing the risk
profiles of cut versus uncut sprouts but exudates released from cut sprouts may
provide nutrients that favour microbial growth (Brandi and Amundson, 2008).
Poor hygienic practices and insanitary production environments and storage
facilities could also lead to sprout contamination. For example, L. monocytogenes is
widely found in nature and can be introduced into sprout production environments
and storage facilities through dust, equipment, raw materials or workers.
Once L. monocytogenes establishes itself in a sprout operation, it can repeatedly
contaminate products and potentially lead to foodborne illness outbreaks.
Considering that sprouts are mostly consumed as RTE foods, contamination
by asymptomatic carriers of pathogens should also be considered (EFSA, 2011).

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Prevention and control measures
4
for seed production and handling

4.1 SEED PRODUCTION

Microbial contamination of seed with zoonotic foodborne pathogens may occur
during cultivation and harvesting, and during processing, conditioning, storage
and transportation. While environmental contamination has been linked to
sprout outbreaks, the vast majority of outbreaks attribute the likely source of
contamination to the seed (EFSA, 2011). The presence of pathogens in or on seed
is amplified by the sprouting process itself. The risk of sprout contamination can be
reduced through the implementation of preventive measures used on farms to avoid
contamination of the seed. Contamination of the seed may occur at any point in
the value chain, during growing, harvesting, milling, sprouting or shipping. Plants
for seed production are grown in typical agricultural environments and potential
sources of contamination in the field include water, improperly managed animal
manure, contact with wild animals and inadequate worker hygiene. Precautions are
required at harvesting, as harvesting exposes the seed to debris and dirt and is likely
to spread contamination throughout the harvested seed. GAPs should be applied
at all stages for seed destined for sprout production, including planting, growing,
harvesting, cleaning, storage and transportation (CFIA, 2018; Jin et al., 2019).
Seed can be produced for a number of different purposes, including as human
food and animal feed, and is generally treated as a raw agricultural product.
There are many agricultural practices that can be used for seed production,
depending on the type of seed being produced. It is anticipated that climate
change will play an increasing role in outbreaks linked to contaminated seed.

15
 For example, the frequency of extreme weather events including hurricanes,
tropical cyclones, tsunamis, monsoons, severe flooding and high winds is
expected to increase (Wu et al., 2016; Uyttendaele, Liu and Hofstra, 2015).
Additionally, ambient temperature increases are expected to lead to prolonged
droughts (Castro-Ibáñez et al., 2015). These events will likely have direct and
indirect impacts on seed production. Bacterial concentrations can increase
by 25- to 30-fold in agricultural fields following extreme precipitation
(Cevallos-Cevallos et al., 2012), and flooding has been linked with an overflow of
untreated human sewage (Kenward et al., 2016). As a result, frequent flooding of
cropland could lead to increased contamination of seed with foodborne pathogens.
Drought also poses direct and indirect threats to seed production. Direct threats
may be caused by increasingly desiccated soil, which when coupled with wind
events may lead to the carriage of bacterial pathogens on dust particles or dried
manure (NSWDPI, 2018) and increased contamination of seed. An indirect
consequence of drought is the reduced availability of clean irrigation water, and
the use of irrigation water of poor sanitary quality could contaminate seed grown
for sprout production, especially in regions already impacted by water quality
issues, including LMICs. Finally, climate change has been reported to increase
the biotic stress of plants, leading to diseased or weakened food crops and an
increased internalization of foodborne pathogens (Garrett et al., 2016) into the
roots, leaves and fruits (Critzer and Doyle, 2010) and potentially the seeds of food
crops. For additional details on the impact of climate change on the production
of fresh produce, please refer to the climate change section of the JEMRA
report “Prevention and control of microbiological hazards in fresh fruits and
vegetables – general principle” (FAO and WHO, 2021b).

4.1.1 Animal and human activities

As with other fresh produce commodities, wild and domestic animals are a main
source of pathogenic zoonotic agents that may lead to contamination in seed.
Livestock production and the presence of wildlife in proximity to, or upstream of
water sources used to irrigate fresh produce can pose a significant risk of pathogen
transfer to produce via aerosols (Dungan, 2010) and fecal deposition (McAllister
and Topp, 2012). Additional sources of foodborne pathogens that can impact
fresh produce include agricultural runoff or bioaerosols from nearby concentrated
animal production operations, overflows from wastewater treatment and septic
facilities, infected farmworkers and untreated manure-based natural fertilizers
(Bozkurt et al., 2021).
All potential sources of environmental contamination should be identified,
assessed and ranked according to risk. For example, primary production should

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not be carried out in areas where the potential for environmental contamination
due to wild or domestic animal intrusion, manure, dust and contaminated water
could lead to the presence of foodborne pathogens in or on seed following harvest.
Where possible, seed producers should conduct an analysis of the previous uses
of the production sites as well as adjacent sites to identify potential microbial
hazards. To the extent possible, steps should be taken to prevent the access of
wild animals and insects to the production area. Additionally, grazing of domestic
animals should not occur in fields while crops are actively being grown for sprout
seed production; this includes animal use to clip back plants to induce seed
production (e.g. alfalfa) (CFIA, 2007). Agricultural runoff and dust contamination
from concentrated animal feeding operations (CAFOs) and flooding by potentially
contaminated water sources should also be prevented (CFIA, 2007).
The scientific literature provides information regarding the routes by which wildlife
and domestic animals contaminate fresh produce with foodborne pathogenic
microorganisms (Langholz and Jay-Russell, 2013; McAllister and Topp, 2012).
The available literature demonstrated that grazing animals are actually helping to
spread pathogens, so animals should not be allowed to graze in fields where seed is
being produced. Additionally, studies should be conducted to understand wildlife
movement patterns and their interactions with human and livestock sources of
foodborne pathogens, and how such interactions affect contamination of fresh
produce (Langholz and Jay-Russell, 2013), including sprout seed.

4.1.2 Manure, biosolids and other natural fertilizers

The prevention of contamination is particularly important during the production
of seed that will be used to produce sprouts for human consumption because of the
potential for pathogens to grow during the sprouting process. There are a variety
of agricultural inputs that can be used as natural fertilizers, including livestock
manure, slurries and biosolids. These natural fertilizers can introduce foodborne
pathogens into the seed production environment. Mitigation and intervention
methods are the same as for production of other fresh produce commodities and
include using only adequately treated or composted manure/biosolids (i.e. they
have undergone treatment to reduce pathogens to levels unlikely to result in
contamination) (Alegbeleye, Singleton and Sant’Ana, 2018; FAO and WHO, 2017).
Physical, chemical or biological treatments such as composting, pasteurization
and heat drying have been proven to be effective in reducing the presence of
pathogens in manure, sewage sludge and other organic fertilizers. In general, it
is recommended not to apply treated natural fertilizers after planting; however,
during the production of seed, treated manures can be applied to the soil during
the growing period if there is no direct contact with the seed.

CHAPTER 4 – PREVENTION AND CONTROL MEASURES FOR SEED PRODUCTION AND HANDLING 17
 If untreated or partially-treated natural fertilizers are used, the time period between
the application and the planting and harvesting of seed should be maximized,
as bacterial pathogens die off over time (EC, 2017). In most international guidance,
a period of 60 days is considered to be the minimum duration. In many countries,
there is national legislation in place that establishes the type of treatments required
for each specific application of organic amendments. If national guidelines
or regulations are available, and include methodologies for assessing vulnerability
and risk, selecting appropriate risk mitigation measures and monitoring the
treatment process, such guidelines should be followed (FAO and WHO, 2019).

4.1.3 Agricultural water

Irrigation water and other sprays can introduce foodborne pathogens into seed,
and the irrigation method will affect the risk of contamination. Water quality
management will vary throughout all operations. The quality of water used should
be dependent on the stage of seed production (i.e. fit for purpose) (FAO and WHO,
2003). For additional details on the appropriate use of water during the production
of fresh produce, please refer to the JEMRA report “Safety and quality of water
used in food production and processing” (FAO and WHO, 2019).

4.1.4 Equipment associated with growing and harvesting

Poorly designed, maintained, cleaned and sanitized equipment can introduce
foodborne pathogens to seed (EC, 2017). The potential also exists for
cross-contamination during harvesting between soil and seed (EC, 2017).
Equipment should be designed or adjusted to protect against pest incursion,
to minimize soil intake and seed damage, and to allow for easy cleaning and, when
necessary, sanitization. Prior to harvest, all debris or soil should be removed from
equipment. All equipment should be thoroughly dry cleaned (to minimize the
presence of water which could lead to microbial growth) between lots of seed,
and sanitized if required. Handling equipment (e.g. augers, conveyors) should be
regularly cleaned and inspected (CFIA, 2007).

4.1.5 Tracking the source of contamination

When contamination of seed is detected, approaches should be developed to
trace pathogens to their root source. To determine the source of contamination,
traceability of seed intended for the production of sprouts for human consumption
is essential. Poor traceability of seed may cause delays in the control of the outbreak
by the competent authorities (EFSA, 2011).
The introduction of methods such as whole genome sequencing (WGS) and
metagenomic sequencing should be used to better understand the originating

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sources of foodborne pathogens that contaminate seed, as a first step in developing
effective approaches to stop such contamination. Understanding the transmission
processes of foodborne pathogens during seed production and the identification
of environmental sources of microbial contamination are essential to manage the
food safety risks associated with the production of fresh produce (Langholz and
Jay-Russell, 2013), including seed.

4.2 SEED HANDLING

(PROCESSING AND CONDITIONING)
Seed handling, including harvesting, threshing and drying, can introduce microbial
contamination. Great efforts should be made to maintain sanitation in seed
drying yards. Exposure of seed to mist, high humidity and fog should be avoided,
as controlling moisture content will decrease microbial growth and survival
(FAO and WHO, 2017).
Seed for sprouting should be free to the extent possible from foreign matter,
including soil, insect fragments, bird and rodent droppings and metal and
glass fragments. Conditioning utilizes a variety of equipment to remove soil,
weed seeds and other debris from seed, and should be carried out in a hygienic
manner employing practices that minimize potential sources of contamination
(CFIA, 2007). Care should be taken during seed processing or conditioning to
avoid contamination. Processing techniques like scarification of the seed will
produce a rough, porous surface in which pathogens can hide and even enter the
seed, making the seed decontamination process less effective and more difficult.
Seed conditioning facilities should ensure that the equipment has not previously
been used to handle animal products, and such equipment should be thoroughly
cleaned and sanitized before cleaning the seed. Any visibly diseased or damaged
seed, which could be susceptible to microbial contamination, should not be used
for sprout manufacture. Seed intended for sprouting should be segregated from
seed to be used as animal feed (e.g. hay production) (CFIA, 2007).
At all times, seed, equipment, storage bins and shipping bags should be protected
from rodents and birds with a complete pest control programme that includes
monitoring, eradication, cleaning, sanitization and record-keeping. Seed destined
for sprouting should be packaged in a hygienic manner in solid bags that are
impermeable to contamination during storage and transportation. Contaminated
or recycled bags should not be employed. In addition, each package should
be labelled with information identifying the source and seed lot. (CFIA, 2007).

CHAPTER 4 – PREVENTION AND CONTROL MEASURES FOR SEED PRODUCTION AND HANDLING 19
 There is a lack of information regarding the impact of various seed production steps
on microbial food safety. More studies are needed to evaluate the best ways to harvest,
thresh and dry seed to reduce the risk of microbial contamination. Additional
studies should also investigate the optimal moisture content to reduce microbial
contamination and how extraneous matter such as soil can be removed from seed.

4.3 STORAGE AND TRANSPORT

Seed may be stored in various ways, including in bags in traditional warehouses,
vertical silos or bins (bulk storage) or horizontally on the floor. Where seed is stored
horizontally, there is a requirement for specially constructed floors and proper
ventilation. Suitable handling practices and techniques for both domestic as well
as industrial storage are required, and safety procedures are therefore mandatory
to prevent microbiological contaminations (Galieni et al., 2020).
During seed storage, animal and insect controls should be implemented (EC, 2017/C
220/03). Temperature and humidity should be controlled and appropriate hygiene
conditions, including cleaning and sanitation (environmental controls), should be
implemented. Storage bins, transport trucks and wagons should be regularly cleaned
and sanitized and should be designed to facilitate cleaning and reduce the potential
for harbouring extraneous material. Storage containers should be bird and rodent
proof or kept in a rodent-free facility. Van der Linden et al. (2013) demonstrated the
long-term survival of enteric pathogens (Salmonella enterica and STEC O157:H7)
on seed stored for up to two years but also showed that the pathogens maintain their
ability to resuscitate and proliferate on the seedling.

4.4 SEED TREATMENT (BY SEED SUPPLIERS)

Due to the risk associated with foodborne pathogen contamination of seed,
it is recommended that the seed be treated prior to sprouting. Ordinarily, seed
treatment is performed by the sprout producer, where the sprouting process takes
place. However, it could happen that seed is treated by the seed supplier. The same
information that applies to the treatment of seed during sprout production applies
to seed treatments performed by the seed suppliers. Treatment of seed must be
effective at reducing the presence of foodborne pathogens, but not so harsh as to
affect the germination of the seed. Similar to other low water activity food products,
disinfection of seed can be challenging, especially considering the impact of the
treatment on seed viability. The majority of studies on seed treatment were designed
to be performed in the sprouting facilities (see Section 5.5). Few published studies
have examined the seed treatment conducted by the seed suppliers, although seed

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pretreated with a mixture of hydrogen peroxide, peroxyacetic acid and acetic acid
is commercially available (ISS, 2022).

4.5 MICROBIOLOGICAL TESTING OF SEED

(AT THE FARM OR BY THE SEED SUPPLIER)
Anticipated concentrations and prevalence of foodborne pathogens present on
seed are low (e.g. Salmonella from seed associated with outbreaks was determined
to be 13 MPN/kg to 16 MPN/kg and 20 MPN/kg to 100 MPN/kg of dry seed
(Fu et al., 2008; Stewart et al., 2001)). Pathogenic bacteria are distributed
heterogeneously in lots of seed (Van Beneden et al., 1999), and may also be
heterogeneously distributed in sprouts and in spent irrigation water (Liu and
Schaffner, 2007; McEgan, 2008). Detecting low levels of foodborne pathogens in
seed prior to sprouting is difficult, as exemplified by a number of outbreaks in
which pathogens were not found in the corresponding seed or sprouts linked to
outbreaks (Mahon et al., 1997; Watanabe et al., 1999).
Effective testing of each seed lot is recommended due to the sporadic nature of
seed contamination (EFSA, 2011). Assuming that pathogens are present in one
25 g sample out of every 1 000 (Montville and Schaffner, 2005), the probability of
detecting foodborne pathogens in 160 samples (25 g) of seed, before sprouting,
was determined to be 0.1 percent (Montville and Schaffner, 2005); to increase the
probability of detection of any pathogen in a seed lot, it is necessary to analyse
many samples (Bylund, 2013). For example, according to the European Food
Safety Authority (EFSA), if one seed per kilo is contaminated, and contaminated
seeds are randomly distributed, then at least three kilos of seed would need to be
analysed in order to ensure that there is a 95 percent chance that the contaminated
seed is detected (EFSA, 2011). Seed lots should be sampled and tested by the seed
supplier rather than the sprout producer to reduce the likelihood of introducing
contaminants into the sprout production area (EFSA, 2011).
Given that pathogens are sporadically distributed throughout a lot of seed and
that they are likely to be present at low concentrations, the practice of sprouting a
sample of seed and analysing the sprouts and/or the spent sprout irrigation water
for pathogens has been suggested as a special case of pooling of seed where the
sprouting serves as a first pre-enrichment step (EFSA, 2011).
Several methods are used to determine the presence, prevalence and concentration
of bacterial pathogens and indicator microorganisms in seed (FDA, 2022a;
Fu et al., 2008). Molecular-based methods (polymerase chain reaction (PCR))
can also be used for the detection of bacterial pathogens in seed (Bylund, 2013).

CHAPTER 4 – PREVENTION AND CONTROL MEASURES FOR SEED PRODUCTION AND HANDLING 21
 The concentration and prevalence of foodborne pathogens in seed is unknown.
This includes variability by seed type and producer. Studies should be conducted to
address this knowledge gap, though the challenges associated with testing seed due
to low microbial prevalence make such studies difficult to perform.

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Prevention and control
5
measures for sprout production
Preventive and control measures need to be put in place to avoid water,
workers, production environments, growth media, or seed serving as the source
of contamination or as a vehicle of cross-contamination. The production process
should be based on an HACCP system, where all the steps are well documented
and potential critical control points (e.g. decontamination of seed) can be identified
and controlled. If a problem is identified, a critical evaluation of all the steps should
be performed. Microbial testing can serve as a verification of the effectiveness of
control measures.

5.1 WATER
It has been demonstrated and stated by several organizations, including
expert groups from FAO/WHO, that water used along the fresh fruit and
vegetable (FFV) supply chain can be a potential source of microbial pathogens
in products at consumption (FAO and WHO, 2021a). Water use in sprout
production is no exception. The MRA 33 FAO/WHO report (FAO and WHO,
2019) introduced the “fit for purpose” concept, establishing that water should
be fit to use for the intended purposes. The main challenge would be to define
the requirements for water quality use along the food chain, because it should
take into account the purpose of the water use, potential hazards associated
with the water use, whether there is any subsequent measure to decrease the
potential for contamination further along the food chain and the end use of the
food product (e.g. eaten raw).

23
 In the case of sprouts, water is used in several operations during production
and processing (e.g. washing, germination, growth, cooling). The water used in
sprouting may spread pathogens from contaminated seed to pathogen-free seed
within the same sprouting batch or contaminate the sprouting equipment, thereby
increasing the total amount of pathogens in the final product (EFSA, 2011).
Process water used in washing and cooling can also be a source of cross-
contamination of fresh produce (FAO and WHO, 2019). The most important risk
factors to be considered include the microbial quality of the water, the stage in the
supply chain, how the water is used, the end-use of the crop and the efficacy of
risk mitigation measures. Sprouts are frequently eaten raw or only slightly cooked,
which implies that there will not be any kill step prior to consumption.
The microbiological quality of the water used in the production and processing of
sprouts should be of a quality that does not constitute a hazard to the safety and
suitability of the final product. The MRA 33 FAO/WHO report (FAO and WHO,
2019) states that water in contact with fresh produce, which is not usually subjected
to an upstream microbial inactivation or reduction treatment, should be of potable
quality during all post-harvest use and handling. Recommendations have also been
provided by the EFSA, indicating that when sprouts are germinated and grown
from seed hydroponically, only potable water should be used during sprouting
(EFSA, 2011). If clean water is used, the microbial properties of the water from that
source should be analysed based on the risk assessment. The same recommendations
are in place for the water used for washing and cooling operations. In this case, if
water is used in contact with large quantities of produce or reused in different
operations, it should be treated and maintained in good microbiological
condition such that no risk to the safety and suitability of food will result from
its use. In general, adequate hygienic conditions for processed water have to be
maintained using food grade disinfectants at validated concentrations to prevent
cross-contamination. The water treatment process should be effectively monitored
to maintain potable water quality during the production and/or processing day.

5.2 WORKERS
Workers can carry pathogens on their skin and hands and in their digestive systems
or respiratory tracts. They can be a vector for transmitting diseases and causing
contamination in sprouts or food contact surfaces. Infected food handlers have
been implicated in many illness outbreaks (Greig et al., 2007). An investigation
of a cluster of E. coli O104:H4 infections linked to a family party where sprouts
were served pointed towards transmission via food items contaminated by a food
handler (Diercke et al., 2013). The possibility of person-to-person transmission

24 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

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of E. coli O104:H4 has been reported whereby patients could acquire hemolytic
uremic syndrome (HUS) by secondary transmission from a person in the household
that was infected by consuming contaminated fenugreek sprouts (Aldabe et al.,
2011; Kuijper et al., 2011).
A healthy, clean and properly trained workforce that follows good worker health
and hygiene practices is critical to ensure that workers do not become a source
of sprout contamination. Operations should establish Standard Operating
Procedures (SOPs) that address worker training, adequate and appropriately
maintained facilities and supplies, as well as company policies on expectations for
worker hygiene, illness reporting and exclusion from work guidelines. Operations
must ensure that visitors are also aware of and comply with these policies and
procedures.

5.2.1 Worker health and hygiene

Persons with symptoms of vomiting, diarrhoea or fever must not perform jobs
that require contact with sprouts or food contact surfaces. Open wounds must be
covered by dry, tight fitting and impermeable bandages or gloves. Ill persons may
be assigned to other tasks but should be restricted from contact with workers who
may come into contact with sprouts or food contact surfaces. Employees must be
instructed to report infectious illnesses or symptoms of illness to the management
(SSA, 2017).
Workers should maintain adequate personal cleanliness and, where appropriate,
wear suitable protective clothing and footwear to prevent contamination of sprouts
or food contact surfaces. Personal effects (e.g. jewellery, watches, purses, backpacks,
clothes) should be removed or covered if they cannot be adequately cleaned and
sanitized while handling sprouts.
Workers must wash and dry their hands thoroughly before starting work,
before putting on gloves, after using the toilet, upon returning to the workstation
after a break or after handling any surfaces or items that could result in contamination
of sprouts. If gloves are used, sprout operations should have a policy to ensure
proper use of gloves. These include washing hands before putting on gloves,
maintaining gloves in an intact and sanitary condition and replacing gloves when
sanitary conditions cannot be maintained.
Sprout producers should have procedures in place to ensure that, following
an injury, any blood or bodily fluids are removed, all affected surfaces are cleaned
and sanitized and all affected products are disposed of (SSA, 2017).

CHAPTER 5 – PREVENTION AND CONTROL MEASURES FOR SPROUT PRODUCTION 25

 5.2.2 Facilities
Sprout producers should provide adequate washing and toilet facilities so that
an appropriate degree of personal hygiene can be maintained. Such facilities should
be suitably located. The restrooms should not open onto the sprout production
areas. Hand-washing stations should be located at all entrances to the sprouting and
packaging areas and should have adequate means for washing and drying hands,
including wash basins, clean running water, soap, toilet paper and single use paper
towels or an equivalent. Toilet facilities must be equipped with hand-washing stations.
The facilities should be appropriately designed to ensure the hygienic removal of waste
and should be maintained in sanitary conditions and in good repair (SSA, 2017).

5.3 PRODUCTION ENVIRONMENT

For the hygienic production of sprouts and to minimize the potential for
cross-contamination, a proper production environment is important to maintain
food safety. Appropriate location and construction of buildings will help protect
against sources of external contaminants which may affect the safety of food.
The appropriate sanitation in place will help minimize the transfer of microbial
contaminants within the facility. Sprout production must be done in a fully enclosed
building. The doors of the production area should not be kept open when not in use
and the doors should be tight-fitting. The windows in the production area should
not be kept open in order to prevent the entry of pests. The zoning of production
and non-production areas must be managed to avoid cross-contamination.
It is recommended that areas where sprouts are processed or stored are separate
from the equipment washing, maintenance and waste areas, laboratories,
offices and toilet facilities (FDA, 2017b).
The potential areas/hotspots for contamination must be minimized by proper
design, which includes the separation of operations and differentiation between
areas in which contamination is likely to occur. Separate storage areas must be
identified for the storage of seed, sprouts and chemicals. In addition, the sprout
production area and packaging area should be in separate rooms.
One of the critical factors for sprout contamination is stagnant water in the
production environment. The construction of floors should be inclined towards
trapped drains and the unidirectional flow of the water/waste in the production
line should be maintained to avoid any chances of contamination. The stagnation
of water on floors may harbour pathogens, particularly L. monocytogenes.
The accumulation of standing water should be minimized in sprout operation
areas where large quantities of water are used during production (SSA, 2017).

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In order to minimize the chances of contamination from the non-production area,
workers involved in sprout operations should have adequate, readily accessible
toilet facilities in close proximity to the production area. Hand-washing stations
should be located in both the production and the packaging areas to facilitate
their use (FDA, 2017a). The equipment and tools required for production must
have a proper design, construction, and workmanship to enable them to be easily
cleaned and properly maintained. Inadequate cleaning and sanitizing of the tools
and equipment can lead to contamination. Inaccessible or hard-to-clean areas may
provide harborage or growth sites for microorganisms. To prevent contamination
or cross-contamination due to the equipment used in the production, it is
recommended that sprout producers install, store and maintain equipment and
tools in such a way as to facilitate cleaning of the equipment and adjacent spaces,
protect against contamination and prevent the attraction and harbourage of pests.
Sprout producers should store equipment and tools in a fully enclosed building to
minimize the potential for contamination (FDA, 2017a).
L. monocytogenes is a pathogen of concern and the target microorganism for
environmental monitoring in sprout production (Goulet et al., 2012; Pouillot
et al., 2012, 2015). An environmental monitoring plan should be designed to
identify L. monocytogenes if it is suspected of being present in the production
areas. As part of the environmental monitoring plan, sprout producers should
also develop a routine sampling plan that includes the frequency, time and date
of the sampling and the test microorganism (Listeria spp. or L. monocytogenes).
When the presence of L. monocytogenes is detected, additional testing should be
done on surfaces and surrounding areas to detect and evaluate the extent of the
problem in the production area. The environmental monitoring plan should also
include a corrective action plan and details on when and how to implement the
corrective actions if the environment for sprout growing, harvesting, packing or
holding areas tests positive for Listeria spp. or L. monocytogenes (FDA, 2017a).

5.4 SOIL/GROWTH MEDIA

Some sprout varieties (e.g. sunflower, peas, buckwheat, daikon) can be grown
in water, soil, substrate or other growth media. These soil and growth media may
be amended with composted animal manure or wastes and may contain
pathogenic bacteria, viruses or parasites (Chen and Jiang, 2017). Foodborne
pathogens, such as STEC O157:H7, Salmonella spp. and L. monocytogenes, present
in manure-amended soil, can survive for long periods of time, under a variety of
conditions (Chen and Jiang, 2014; Chen, Kim and Jiang, 2018; Gurtler et al., 2018;
Jiang et al., 2004). The transmission of STEC O157:H7 from soil amended with

CHAPTER 5 – PREVENTION AND CONTROL MEASURES FOR SPROUT PRODUCTION 27

 contaminated manure to lettuce plants grown on these soils has been demonstrated
(Islam et al., 2004; Solomon, Yaron and Matthews, 2002). STEC O157:H7 entered
the lettuce plant through the root system and migrated throughout the edible
portion of the plant (Solomon, Yaron and Matthews, 2002).
Natural fertilizers of animal origin must be treated to reduce or eliminate pathogens
of public health significance before their application for growing fresh fruits and
vegetables (FAO and WHO, 2017; FDA, 2015a). All the information included
in section 4.1.2 (Manure, biosolids and other natural fertilizers) is also relevant
for sprout production in soil and substrate. A variety of treatment processes
and practices are available, including physical (e.g. heat), chemical (e.g. high
alkaline pH), and biological (e.g. composting) processes (Chen and Jiang, 2014,
2017; Gurtler et al., 2018). Many factors may affect the reduction and survival
of bacterial foodborne pathogens during the composting or heat treatment processes.
It is critical that the effectiveness of treatment against pathogens be thoroughly
assessed and demonstrated before broad commercial application (Chen and
Jiang, 2017). As previously indicated, if national guidelines or regulations are
available, and include methodologies for assessing vulnerability and risk, selecting
appropriate risk mitigation measures and monitoring the treatment process, such
guidelines should be followed (FAO and WHO, 2019).
Sprout producers must implement measures to prevent soil or growth media from
becoming a source of contamination or cross-contamination in sprouts, on food
contact surfaces or in the production environment. Growers should make sure that
the received natural fertilizers of animal origin have been properly treated using a
scientifically valid method, and are handled, conveyed and stored in a manner and
location that minimizes the risk of contamination.
Activities involving the handling of growth media or the growing and packing
of media-grown sprouts should be separate from those involving other sprouts
(e.g. hydroponically grown sprouts), either by location or by time. Measures need
to be in place to prevent cross-contamination of the growing areas by movements
of workers, tools or equipment. All surfaces must be cleaned and sanitized after
handling growth media or media-grown sprouts.

5.5 SEED
Seed has been identified as the primary source of contamination in sprout-associated
outbreaks of foodborne illness (Bazaco et al., 2021; Dechet et al., 2014). As a raw
agricultural product, seed can become contaminated in several ways. The most
significant risk factors are associated with the effect of agricultural practices on

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seed production, storage and distribution, contaminated irrigation water and/or
manure, as well as the presence of dust, soil, birds and rodents in storage facilities.
During warehouse storage, seed stored in open containers can be exposed to
rodents, birds, faeces of farmyard animals and insect pests which are all potential
vectors of contamination (EFSA, 2011).
Seed can be sold directly to sprout producers for sprouting or to seed
distributors. The seed is not only used for sprout production, as it is often used
for other purposes (e.g. edible seeds, animal feeds, oil production, horticulture)
(EFSA, 2011). This is why it is very important to ensure that seed is obtained from
producers or distributors that follow GAPs and GHPs during the production,
storage, distribution and commercialization of the seed. In most countries, there
are codes of practices and guidelines on preventing field contamination during
sprout and seed production (EC, 2017; FDA, 2017a). However, imported seed may
come from countries where guidelines are not available. For this reason, some
countries have established specific certification requirements for sprouts or seed
intended for the production of sprouts that are imported from other countries.
The certificate attempts to guarantee that the sprouts or seed produced in exporting
countries are produced under conditions that comply with the general hygiene
provisions for primary production and associated operations set out in the codes
of practices. The certificate also implies that consignments of seed for sprouting
destined to be exported to these countries may be tested for Enterobacteriaceae to
verify the hygienic conditions of production prior to exportation. The level of these
bacteria in seed cannot exceed 1 000 cfu/g (EC, 2013).
Seed is received in bags. Very often, a bag of seed received at the sprout operation and
used for a sprout production batch is a mixture of various lots of seed from different
sources. When seed arrives at a sprout operation, it should be inspected for physical
damage and signs of contamination. In most cases, seed may be stored for long
periods of time (especially in sprout operations with small production volumes)
before being sprouted, either in the plant or at some steps of the seed distribution
chain (e.g. fenugreek seed from 2009 were sprouted in 2011 (EFSA, 2011)).
Once received, seed should be stored and handled in a manner that will avoid
damage, prevent the growth of microorganisms and protect it from pests and other
sources of contamination.
Due to the difficulty of obtaining seed that can be guaranteed as pathogen free,
decontamination of seed prior to the sprouting process is recommended, where
appropriate, to reduce the risk of foodborne illness. In the Scientific Opinion published
by the EFSA (2011a), there is a good overview of alternative decontamination
treatments that can be applied to seed and sprouts. Many seed decontamination
treatments, including chemical, biological and physical methods (Ding, Fu and

CHAPTER 5 – PREVENTION AND CONTROL MEASURES FOR SPROUT PRODUCTION 29

 Smith, 2013; Sikin, Zoellner and Rizvi, 2013) are available. Chemical treatments
include calcium hypochlorite, chlorine dioxide, acetic acid, as well as other treatments
such as ozone, antimicrobial polymers, plasma-activated water and oxychloro (Kumar
et al., 2006; Machado-Moreira et al., 2021; Mir et al., 2021). Biological methods
include the use of antagonistic bacteria (e.g. lactic acid bacteria, Pseudomonas
spp., Bacillus spp.) and bacteriophages (Kimmelshue, Goggi and Cademartiri,
2019; Kocharunchitt, Ross and McNeil, 2008; Ye et al., 2010; Zhang, 2017).
Physical approaches include low heat (pasteurization), irradiation, high pressure,
UV light and cold atmospheric plasma (Charoux et al., 2020; Miyahira and Antunes,
2021). The effectiveness of treatments is highly variable between published studies
(Montville and Schaffner, 2005).
The scientific literature contains many examples of studies conducted to evaluate
seed decontamination strategies. However, the majority of works aimed at the
validation of seed treatment approaches are based on laboratory evaluations of
inoculated seed, and it is unclear whether the results of these studies are applicable
to naturally contaminated seed and/or use on commercial scales. Additionally,
the costs of the treatments are unclear.
The most frequently used decontamination treatments applied to seed before
sprouting are chemical sanitizers (e.g. 20 000 ppm free chlorine for 20 minutes).
Some authors have also reported that the combination of these treatments with hot
water treatments is very effective e.g. 85 °C for 40 seconds followed by soaking in cold
chlorine water (2 000 ppm for 30 s) (Bari et al., 2010). It should be considered that,
despite considerable efforts, chemical methods of disinfection cannot be relied on as
methods capable of ensuring a pathogen-free state for all seed types. There are some
disinfection treatments that have been shown to consistently achieve a substantial
reduction in pathogen numbers, only managed by combining relatively high
concentrations (> 10 000 ppm) and contact times (10 minutes) (Suslow et al., 2002).
Measures to prevent the introduction of pathogens in sprout production (including
primary production of seed) remain of the utmost importance (EFSA, 2011).
During seed decontamination, producers should ensure that all containers
used for microbiological treatment are clean and sanitized prior to use. If liquid
decontamination methods are utilized, seed should be agitated well in large
volumes of an antimicrobial agent to maximize treatment efficacy. The duration
of treatment and the concentration of the antimicrobial agent used should be
accurately measured and recorded. Following decontamination, steps should be
taken to avoid post-processing contamination or recontamination of treated seed.
The antimicrobial agent should always be used according to the manufacturer’s
instructions, and, as appropriate (depending on the treatment method), following
decontamination, seed should be thoroughly rinsed with water of appropriate

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quality (ideally potable water or at least clean water). Rinsing should be repeated
as necessary to eliminate the antimicrobial agent (FAO and WHO, 2017).
It is important that the impact of the decontamination treatment on the
germination rate of the seed be considered. In many cases, before a treatment can
be implemented in the industry, it has to be validated for each type of seed variety,
as not all seed types will be suitable for the same treatment.

5.6 MICROBIAL TESTING

Currently, the available seed treatment methods are not able to eliminate pathogens
in or on seeds. Pathogens that survive seed treatment could grow to high numbers
during sprouting. Microbial testing can be a part of the multi-hurdle approach to
prevent potentially contaminated sprouts from entering the marketplace. It is also
a way to verify that neither the seed used for sprouting nor the production process
contributed to the contamination of the sprouts.

5.6.1 Target for testing and sampling plan

Microbial testing can be carried out at various stages throughout sprout
production. Samples of incoming seed, in-process sprouts, spent sprout irrigation
water, finished products or from the environment (swabs) can all be analysed
(EC, 2073/2005).

5.6.1.1 Seed
Although contaminated seed is the likely cause of most reported sprout outbreaks,
seed testing has often failed to detect the presence of pathogens due to the low level
and sporadic nature of contamination. The European regulation, EC 2073/2005,
requires sprout operations to conduct preliminary testing of a representative sample
of all batches of seed used for sprouting. A representative sample shall include at
least 0.5 % of the weight of the batch of seed in sub-samples of 50 g or be selected
based on a structured, statistically equivalent sampling strategy. The regulation also
requires that testing be performed by sprouting out the seed samples under normal
sprouting conditions. The regulation allows exemption from this requirement
either if the sprout operation implements a food safety management system that
will reduce the microbiological risk of the seed or if the results from consecutive
testing of the sprouts met the microbiological criteria (EC, 2073/2005).
The “Code of Hygienic Practice for Fresh Fruits and Vegetables” (FAO and WHO,
2017) recommended that seed screening be conducted by seed distributors and
that the seed sample selected for testing should be sprouted prior to analysis

CHAPTER 5 – PREVENTION AND CONTROL MEASURES FOR SPROUT PRODUCTION 31

 to increase the likelihood of detecting pathogens, if present. An example of such
testing procedures using 3 kg of seed collected from each bag of an entire shipment
is available for reference (ISS, 2021).
Screening seed for pathogens by seed suppliers will prevent the use of contaminated
seed by consumers who sprout seed at home. Some of the cases linked to the 2011
fenugreek sprout outbreak were due to consumption of self-cultivated sprouts
from seed mixtures containing contaminated fenugreek seed (BfR, 2011).

5.6.1.2 Spent sprout irrigation water or in-process sprouts

Testing spent sprout irrigation water or in-process sprouts collected during
sprouting increases the likelihood of detecting the pathogens that may be present
in seed. It also enables early detection of contamination in the production batch
before products enter the marketplace. Testing spent sprout irrigation water is
preferred over testing sprouts because water may pick up bacteria as it passes
through the production batch, making it easier to collect a representative sample
(FDA, 2017a).
Sprout producers should establish a written sampling plan that includes procedures
for when, what and how to collect samples. Procedures for holding production
batches until negative test results are received (hold and release) should also be in
place.
Samples must be collected aseptically by trained personnel to ensure that the sample
collection process does not contaminate the sample or the production batch being
sampled. The containers, equipment and tools used for sample collection should
be sterile (FDA, 2017a).
Samples of sprouts or spent sprout irrigation water should be collected when the
level of pathogen, if present, is likely at its highest. Collecting samples as early
as 48 hours after the start of sprouting has been recommended, although the
optimal time for sample collection may vary depending on the type of sprouts and
sprouting practices (CFIA, 2018; FDA, 2017a; SSA, 2017).
The volume of sample collected should be sufficient to be representative of the
production batch and for testing target pathogens. Different sample sizes or
volumes and sampling frequencies are recommended by different agencies. In
the United States of America, the FDA recommends that 1.5 L of spent sprout
irrigation water be collected from each production batch of sprouts for testing
for STEC O157:H7 and Salmonella species. When sampling in-process sprouts,
at least 30 sub-samples, 50 g each, are to be collected from multiple locations in
the growing unit (FDA, 2017a, 2015a). The Canadian Food Inspection Agency
(CFIA) recommends collecting 1 L of spent sprout irrigation water or five samples

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of sprouts (200 g each) from each production batch (CFIA, 2018). In Europe,
Regulation EC 2073/2005 on microbiological criteria for foodstuffs recommends
that sprout producers collect five samples of 200 ml each if spent sprout irrigation
water is analysed. Samples must be collected for microbiological analysis at least
once a month at the stage where the probability of finding STEC and Salmonella
spp. is the highest, and in any case not before 48 hours after the start of the sprouting
process (EC, 2073/2005).

5.6.1.3 Finished products

The EC 2073/2005 regulation requires that ready-to-eat sprouts must comply
with the food safety criteria, i.e. free of Salmonella spp. and STEC O157, O26,
O111, O103, O145, O104:H4. Five 25-g samples of finished sprouts will need to
be analysed for Salmonella spp. and another five samples (25 g each) of sprouts
be analysed for STEC O157, O26, O111, O103, O145 and O104:H4. If a sprout
producer has a sampling plan that includes sampling procedures and sampling
points for the spent sprout irrigation water, the sampling requirement for
ready-to-eat sprouts may be replaced with the analysis of five samples (200 ml
each) of spent sprout irrigation water. The microbiological criterion, in this case,
is the absence of Salmonella spp. or of STEC in 200 ml of spent sprout irrigation
water (EC, 2073/2005).

5.6.2 Testing laboratories

All microbial testing for pathogens should be conducted by a qualified laboratory
with the following criteria (CFIA, 2018; SSA, 2017):

• The laboratory is accredited, for example, to the ISO/IEC 17025 standard for
the methods specified.
• The laboratory is staffed by personnel with training and experience in analytical
microbiology techniques to ensure that tests are performed correctly and that
all appropriate safety precautions, including appropriate waste disposal, are
followed.
• The laboratory has appropriate resources and is able to demonstrate that
a quality management system is followed.
• If microbial analysis is done by the sprout producer, the in-house laboratory
must be physically separated from the sprout production facility to prevent
cross-contamination. The laboratory facilities, personnel, and quality
management system must meet the same criteria required for independent
laboratories to ensure that testing is reliable and does not create food safety
hazards.

CHAPTER 5 – PREVENTION AND CONTROL MEASURES FOR SPROUT PRODUCTION 33

 5.6.3 Test methods
The FDA Produce Safety Rule (FDA, 2015a) requires that spent sprout irrigation
water (or in-process sprouts) from each production batch be tested for E. coli
O157:H7 and Salmonella spp. using either the methods of analysis specified
(FDA, 2015b) or scientifically valid methods that are at least equivalent to the
prescribed methods in accuracy, precision and sensitivity. The EC 2073/2005
regulation specifies reference methods for testing of Salmonella (EN ISO 6597-1)
and STEC (CEN/ISO TS 13136) but states that the use of alternative analytical
methods is acceptable when the methods are validated against the reference
methods. Alternatively, the methods shall be validated according to internationally
accepted protocols and their use authorized by the competent authority (EC, 2005).
Technological advances have resulted in a wide range of rapid methods for the
detection of foodborne pathogens (Law et al., 2015; Melo, 2016; Umesha and
Manukumar, 2018). Many of these methods are commercially available (Mangal et
al., 2016; USDA, 2020). Commercial test kits come with various assay formats and
detection principles (Fu et al., 2022). Immunoassay-based tests employ specific
antibodies that recognize target pathogens. Molecular assays target specific
nucleic acid sequences in microorganisms. The enrichment conditions used vary
depending on test kit and target pathogen. They can involve multiple or single
steps with times ranging from a few days to as short as 6 hours, making same-day
detection possible. Commercial test kits are packaged with ready-to-use supplies
and reagents and are often accompanied by automated instruments and software
that simplify the analysis and interpretation of test results.
Comparative studies have demonstrated that many commercial test kits, including
lateral flow devices, enzyme immunoassays and molecular assays, are able to detect
low levels of Salmonella or STEC O157:H7 in alfalfa spent sprout irrigation water.
Enrichment conditions play a key role in determining the performance of the tests
and the success of confirmation (Fu et al., 2022). However, very few test kits have
been validated through a formal collaborative study as per internationally accepted
protocols for the detection of foodborne pathogens in sprouts or spent sprout
irrigation water. None of the currently available test kits are validated against the
methods prescribed in the FDA Produce Safety Rule.
The United States Food and Drug Administration (FDA) has determined that
several AOAC Official Methods are “scientifically valid” and “at least equivalent
to the specified standard methods” (FDA, 2018). The CFIA specifies a number of
commercial test kits for detection of Salmonella and STEC O157:H7 in sprouts or
spent irrigation water samples (CFIA, 2018).

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Sprout growers should verify that the methods used by the lab are either the
methods specified in the regulation, alternate methods that have been scientifically
validated and shown to be at least equivalent to the standard methods or methods
that have been authorized by the competent authority.

5.6.4 Corrective actions

Sprout operations should have a written corrective action plan in place for
responding to positive test results. Recommended corrective actions include the
following (SSA, 2017):

• Discard any sprout production batch that tests positive for pathogens.
• Evaluate other sprout production batches that have contacted tools
or equipment shared with contaminated products for potential contamination.
• Thoroughly clean and sanitize anything in the sprout operation that came into
contact with the contaminated production batch or its spent irrigation water.
• Discard or return the seed lot used to produce the contaminated sprouts to the
supplier to be diverted to non-food use, unless it is proven that the seed lot is
not the source of the pathogens found in samples that tested positive.
• Notify seed supplier regarding positive test results so that the supplier may
take appropriate actions (e.g. informing other growers that use the same seed
lot).
• Perform other actions to prevent recurrence of contamination, e.g. re-evaluate
control measures and/or cleaning and sanitizing procedures, retrain employees
on proper seed treatment and handling procedures.

5.7 POST-HARVEST STORAGE

Sprouts are generally consumed fresh and, to prevent their growth and retain
quality (microbial, and nutritional), they are stored at low temperatures (Świeca and
Gawlik-Dziki, 2015). Rapid cooling is essential to accomplish the full storage potential
of sprouts. Current industry practice suggests storing finished sprout products at
between 0.5 °C to 4 °C. The shelf-life for sprouts under these storage temperatures
ranged from 7 days for mung beans and 14 days for other green sprouts (e.g. alfalfa,
clover, broccoli) (ISGA, 2022). However, previous studies highlighted that under
these conditions, most sprouts may be expected to retain acceptable quality for
5 to 9 days. The shelf-life at 2.5 °C has been described as being less than 5 days,
and at 5 °C and at 10 °C it is less than two days (Suslow and Cantwell, 2000).
The high respiration rates and perishable nature of sprouts demand distribution and
short-term storage at 0 °C at 95 to 100 percent relative humidity (BMT, 2022).

CHAPTER 5 – PREVENTION AND CONTROL MEASURES FOR SPROUT PRODUCTION 35

 When sprouts are stored, the arrangement of products should allow for good air
circulation and rapid cooling. As sprouts are still respiring, they can generate heat,
even in a low-temperature room. The storage of sprouts in small containers and
good air circulation help prevent “hot spots” in a batch of sprouts that may result
due to heat generated by the still living sprouts (FDA, 2017a).
The safety measures to reduce contamination are temperature control, controlled
humidity, insect-free and proper hygiene conditions for storage. There is also the
need to optimize the storage conditions that allow the chemical composition of the
package headspace to be maintained during their shelf-life. The continuity of the
cold chain is required as much as possible when staging products to prepare them
for loading onto delivery trucks (FDA, 2017a).

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Prevention and control
6
measures during distribution
and at point-of-sale
Distribution covers all the steps from production to the point-of-sale.
After production, finished sprouts are usually packed into containers at the sprout
growing operation or transported in bulk to another location to be packed before
being placed at the point-of-sale or packaged in individual servings for direct sale
to consumers or food service establishments. Distribution of sprouts includes
activities such as loading and unloading of produce into and out of a transport
vehicle; the transport, placement and storage in the receiving facility; and storage
(FDA, 2017a). Sprouts are usually stored under refrigerated conditions, and it
has been demonstrated that the use of modified atmospheres (5 percent O2 and
15 percent CO2) is beneficial for extending the quality of the product (Suslow and
Cantwell, 2000). These conditions maintain high relative humidity, and bacterial
growth will depend mostly on storage temperature. This is why the problems
associated with the distribution and storage of sprouts are mainly linked to the
maintenance of the cold chain (EFSA, 2011). Vehicles used to transport sprouts
should be refrigerated to avoid temperature increases. However, refrigerated
temperatures do not prevent the growth of psychotropic microorganisms, such as
L. monocytogenes.

37
 6.1 MITIGATION/INTERVENTION MEASURES
The main prevention and control measurements to minimize contamination of
sprouts during distribution and at retail and food service establishments are:

• Temperature control: most guidelines recommend a storage temperature

as low as possible (< 5 °C) to avoid the growth of microorganisms.
Although the survival and growth patterns of L. monocytogenes and other
microorganisms such as STEC O157:H7 are dependent on the vegetable
type, package atmosphere and bacterial strain, it has been demonstrated that
reducing the storage temperature from 8 °C to 4 °C reduced the growth of
these microorganisms on packaged RTE vegetables (FDA, 2003; Francis and
O'Beirne, 2001b).
• Hygiene maintenance: all the facilities, equipment, containers, crates, vehicles
and vessels used to transport sprouts and seed should be kept clean and,
where possible, disinfected in order to prevent microbiological contamination
during transport (EC, 2017).
• Shelf-life means either the time corresponding to the period preceding the
“use-by” or the minimum durability (“best before”) date. Date of minimum
durability (“best before”) means the date until which the food retains
its specific properties when properly stored. This period can therefore
be considered as relating to the quality of foods. In the case of foods which,
from a microbiological point of view, are highly perishable and are therefore
likely after a short period to constitute an immediate danger to human
health, the date of minimum durability shall be replaced by the “use-by” date
(EFSA, 2020).
• In most countries, sprouts require a “use-by” date. Xylia et al. (2021)
demonstrated that the expiration date and relevant shelf-life of processed
vegetables are important parameters to be considered when post-harvest
management is applied to these products, ensuring safety and quality.
Therefore, it is highly recommended that consumers do not eat sprouts that
are past their use-by date and, during their shelf-life, keep them refrigerated at
5 °C or below and consume them within two days.
• Relevant information that producers should provide to the consumer to
ensure the safety of sprouts during the storage, handling and preparation of
the product includes: (1) recommended temperature of storage; (2) use-by
date; and (3) cooking instructions, which should be included on the label if
the product is intended to be consumed as non-RTE.
• To avoid cross-contamination, the food contact surfaces of tools and
equipment used in contact with the sprouts should be cleaned and sanitized.
This includes such surfaces during transport and storage.

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• Use of water misters for maintaining the humidity of unpackaged sprouts at
retail: if unpackaged sprouts are displayed for retail, the quality of the sprouts
may deteriorate rapidly due to low humidity and wilting of the product.
This can be prevented by using misters, which increase the humidity around
the product. However, food safety should not be compromised by the use of
misters. The temperature should be kept as low as possible, the water used for
the misters should be fit-for-purpose, the equipment used for misting should
be properly cleaned and maintained and excess water should be drained away
from the products.
• In-restaurant sprouting: follow similar interventions recommended for sprout
producers, including seed source, seed treatment (if appropriate), and spent
sprout irrigation water testing (samples to be tested by contract labs, not in
house).
• Consumers have reported food handling practices that could result in
cross-contamination in personal kitchens. The lack of appropriate hand
washing, as well as the presence of high bacterial counts on sponges and
kitchen sinks, cutting boards, and countertops, have been highlighted as
critical points to control to avoid cross-contamination.
The goal of prevention and control measures during distribution and at retail and
foodservice establishments is to identify the potential sources of contamination
throughout these stages of the food chain so that they can be monitored and
controlled. The aim of applying such prevention and control measures is to reduce
the food safety risks to the public, thus reducing the risk of foodborne outbreaks.

6.2 AVAILABLE DATA

Available data on prevention and control measures during distribution and at
retail and food service establishments for sprouts are mostly related to the survival
of specific foodborne pathogens (e.g. L. monocytogenes, Salmonella, STEC) during
storage. Several research papers have evaluated the growth rate of L. monocytogenes
in different types of sprouts (Aytac and Gorris, 1994; Bennik et al., 1999; Francis
and O’ Beirne, 2001a, 2001b; Lee et al., 2002; Molinos et al., 2005; Thomas et al.,
2003; Tian et al., 2012). However, the information is not complete as more data are
needed to determine the potential growth at abusive temperatures (> 8 °C).

CHAPTER 6 – PREVENTION AND CONTROL MEASURES DURING DISTRIBUTION AND AT POINT-OF-SALE 39

 6.3 UNCERTAINTY AND DATA GAPS

• Data gaps in this area are significant. The experts recognize that there is a lack
of data for many relevant aspects, including the fate of foodborne pathogens
naturally occurring on seed. The pathogen level and prevalence might vary
between different types of seed, but they have not been well-documented.
• The fate of pathogenic bacteria on sprouts during storage at different
temperatures, particularly at abusive temperatures, is not documented.
Specifically, there is uncertainty regarding the increase in risk due to the
differences in growth rates for certain foodborne pathogens between 5 °C and
8 °C.
• Some sprouts may be exposed to some heat during preparation before
consumption (e.g. stir-fried). However, the impact of these heat treatments on
bacterial pathogens is not known.

40 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

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Records and traceability
7
Traceability allows a food to be identified through all stages of production,
processing and distribution, thereby allowing rapid reaction in the event of
foodborne illness outbreaks (EC, 2013). Based on previous experience in outbreak
investigations, it has been demonstrated that the traceability of certain foods of
non-animal origin may assist in the removal of unsafe food from the market,
thereby protecting consumers. Therefore, traceability can be considered as an
efficient tool to ensure food safety because rapid tracing of the commodities
concerned in an outbreak is essential to limit the public health impact. In many
countries, there is already legislation that provides the general requirements for
the traceability of food, which should be established at all stages of production,
processing and distribution (EC, 2017/C 220/03).
The traceability of seed intended for production of sprouts for human consumption
is of great importance in establishing the microbial quality of the seed and for the
implementation of food safety management measures (EFSA, 2011). Seed used for
sprouting is very often imported from other countries. In fact, the 2011 E. coli
O104 outbreak investigation in Germany and France suggested that imported
seed in 2009, contaminated prior to leaving the importer, was the most likely
cause of the outbreak (EFSA, 2011). It has been suggested that the use of imported
seed represents an obstacle for the rapid tracing of the source of the outbreak
(EFSA, 2011). This is why some countries have established specific rules for the
traceability of sprouts and particularly of seed intended for the production of
sprouts. However, it should be taken into account that there may be difficulties in
the traceability of sprouts from the point of seed production to point-of-sale and
to the consumer.

41
 7.1 MITIGATION/INTERVENTION MEASURES
Sprout and seed producers should ensure that records and recall procedures are
in place to effectively respond to health risk situations. Procedures should enable
the complete and rapid recall of any implicated seed. The procedures should also
assist in providing detailed information for the identification and investigation
of any contaminated seed and sprouts.
Several guidance documents are already available where the most relevant measures
to ensure traceability have been described (ESSA, 2017; FAO and WHO, 2017;
SSA, 2017). The European Sprouted Seeds Association (ESSA) hygiene guideline
for the production of sprouts and seed for sprouting published by the European
Union (ESSA, 2017) highlights the most important ones.

• Sprout producers should only purchase seed from trusted suppliers that
have procedures in place to assure good hygienic production of the seed and
traceability of the seed lots.
• If possible, when seed for the purpose of sprouting is imported, a consignment
of seed should be accompanied by an import certificate during all stages of
trade.
• When traders are involved in the supply chain of seed for sprouting, they must
also follow the same traceability requirements.
• All the relevant information regarding the seed lot should be provided by the
seed supplier to the sprout producer. This information includes:
> name of the product including the Latin name (taxonomic name);
> identification number or equivalent lot reference;
> name of the supplier;
> name and address of the recipient (if a forwarder or agent is used: name
and address of the agent or forwarder);
> date of shipping; and
> quantity supplied.
• Seed and sprout producers should have a system to effectively identify a seed
lot, trace their associated production sites and agricultural inputs, and allow
for the physical retrieval of the seed in the event of a suspected hazard.
• Seed production and distribution practices should be in place to minimize the
quantity of seed identified as a single lot and avoid the mixing of multiple lots
of seed, which would complicate recalls and provide greater opportunities for
cross-contamination.
• The customer or next person in the supply chain should receive all the
information relevant to them to handle, store, process, prepare and display the

42 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
 product safely and correctly. Where appropriate and useful, this information
can be included as part of the packaging label.
• Recording and traceability requirements should be followed throughout the
entire production process and records should be kept until it can reasonably be
assumed that the sprouts have been consumed. Traceability codes or numbers
printed on the sprout packaging material may facilitate recalls in the event that
food contamination occurs.
• The information may be kept on records and transmitted in an appropriate
form, provided it is easily retrievable by the Food business operator (FBO)
to whom the seed or sprouts have been supplied. The FBO must also provide
the information to the competent authority, upon request, without undue
delay. For instance, in the event that a sprout producer detects a positive for
a foodborne pathogen in the spent sprout irrigation water, this information
should be rapidly transferred to the seed supplier to proceed with recalling all
the seed in the implicated lot.
• Once on the market, products should be correctly labelled to facilitate
traceability and recall where necessary. Inclusion of the identification or
sprout batch code, as well as the name and address of the producer on the
packaging label, may facilitate traceability and recall.
• Where a lot of seed has been recalled because of a health hazard, other lots
of seed produced under similar conditions (e.g. on the same production sites
or with the same agricultural inputs) and which may present a similar hazard
should be evaluated for safety. Any lot of seed presenting a similar risk should
be recalled. Blends containing potentially contaminated seed should also be
recalled.
The main objective of traceability is to make it possible, at any moment during the
physical flow of the production process, to know which batch of sprouts originates
from which immediate supplier. It is clear that digital traceability represents
a good alternative to more traditional handwritten systems. Digital traceability
is the process of tracking a product via digital systems, removing the risk of human
error. Digital traceability can alleviate and reduce many of the agrifood sector’s
most pressing risks. The Traditional Internet of Things (IoT) traceability systems
provide practical solutions for quality monitoring and traceability of food supply
chains (Feng et al., 2020). Recent studies have demonstrated that blockchain is a
pioneering technology with great potential for improving traceability performance
(Galvez, Mejuto and Simal-Gandara, 2018).

CHAPTER 7 – RECORDS AND TRACEABILITY 43

 7.2 UNCERTAINTY AND DATA GAPS
There is still a lack of information regarding the benefits that the implementation
of digital traceability could provide to this sector. There are very high expectations
about the improvements that this new technology can provide to the sector.
However, the use of blockchain technology still has some barriers, such as high
prices, accessibility and acceptance, which has hindered its implementation in the
agrifood sector. However, the use of blockchain-based traceability management
seems to be imminent.

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Training
8
Proper training is imperative for personnel involved in the production of safe food.
This is particularly important in the production of sprouts, which are produced
under conditions that support the proliferation of bacterial pathogens and where
hygienic interventions can be complicated and technical. Many outbreaks of
foodborne illness have been associated with the consumption of contaminated
sprouts, highlighting the need for improved awareness of hygiene and the adoption
of hygienic practices along the production chain.
The US Food and Drug Administration has published guidance for the sprout seed
industry and provides firms with recommended steps to prevent contamination
throughout the production chain of seed for sprouting. The publication Reducing
Microbial Food Safety Hazards in the Production of Seed for Sprouting (FDA, 2022b)
highlights the need to take steps to educate and train personnel who have food
safety responsibilities in the principles of food hygiene, food safety and personal
health and hygiene. For example, seed producers, handlers and distributors should
be aware of GAPs and their role and responsibility in producing and protecting
seed intended for sprouting from contamination.
Few training initiatives have focused on the production of sprouts and seed for
sprouting. Such training is crucial, and should extend along the entire sprout supply
chain, from the production of seed for sprouting, through to the production of
sprouts and their handling at point-of-sale. There is clearly a need to create a core
curriculum that can be delivered to stakeholders involved in sprout production.
It should cover the principles of food hygiene and food safety. Sprout producers
should follow GHPs, with training in hygienic production of sprouts – including
interventions designed to reduce growth of microbiological hazards. Such training
should cover seed sourcing and storage, seed treatment, sampling and microbial

45
 testing, cleaning and sanitizing and record-keeping. Equally important is guidance
on personal hygiene and maintaining hygienic working environments.
The Sprout Safety Alliance at the Illinois Institute of Technology (https://www.
ifsh.iit.edu/ssa) currently delivers a two-day Sprout Grower Training Course with
a curriculum that is recognized by the FDA. The core curriculum “Safer Sprout
Production for Produce Safety Rule Compliance” (SSA, 2017) is divided into five
segments:

• An overview of the course and the provisions in the Produce Safety Rule that
are applicable to sprout operations;
• An overview of the different types of food safety hazards associated with
sprouts and the importance of their control;
• Maintaining a hygienic production environment, including proper operation
construction, water safety, employee health and hygiene, cleaning and
sanitizing procedures and verification, and environmental monitoring for
Listeria in a sprout operation;
• Sprout specific requirements, including seed purchasing, receiving and storage,
seed treatment, and spent sprout irrigation water or in-process sprout testing;
• Additional control programmes (e.g. employee training, product labelling,
trace and recall procedures, sanitary transportation, allergen controls, and
food defence) and record-keeping requirements.
Successful completion of the programme assists producers in understanding the
regulatory requirements in the United States of America and implementing best
practices for enhancing sprout safety.

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Annexes
 Annex 1

Response to the Codex

Committee on Food Hygiene
(CCFH) regarding specific
interventions for sprouts
The following questions posed on 27 July 2021 by the CCFH E-Working Group
(EWG) for the development of ‘Guidelines for the control of STEC in raw beef,
fresh leafy vegetables, raw milk and raw milk cheeses, and sprouts’ were addressed
by the Joint FAO/WHO Expert Meeting on Microbiological Risk Assessment
(JEMRA) on the Prevention and Control of Microbiological Hazards in Sprouts.
Q1. Most control measures in this Annex (the question refers to Annex 2 ‘Fresh
leafy vegetables’ of the draft ‘Guidelines for the control of STEC in raw beef, fresh
leafy vegetables, raw milk and raw milk cheeses, and sprouts’) are not specific to
STEC (and thus information in the Code of Hygienic Practice for Fresh Fruits and
Vegetables would suffice). JEMRA - Please provide input on control measures that
have been studied scientifically with respect to controls for STEC and thus warrant
inclusion. (These measures may also control for other pathogens, but we need to
know if there is sufficient scientific information related to controls for STEC to
warrant including them in this Annex.)
A1. Many potential measures have been scientifically studied with respect to controls
for microbiological hazards in sprouts. Based on the experts’ opinions, while much
of this research was not carried out with STEC, the conclusions are valid for STEC
control as well. Specific experiments using different STEC serotypes are not necessary;
there is no evidence to indicate that different STEC serotypes behave differently
from one other, or from other enteric pathogens like Salmonella, in response to these
control measures. The most significant control measures include:

• Ensuring seeds intended for sprouting are produced under Good Agricultural
Practices (GAPs).
• Ensuring water that comes into contact with the seed production crop directly
is fit-for-purpose.

61
 • Seed treatment to reduce microbiological foodborne pathogens on seed
surfaces.
• Sampling and testing of spent sprout irrigation water for bacterial pathogens
of concern.
• Maintenance of a sanitary sprout production environment.
• Maintenance of the cold chain at every stage following sprouting.
Q2. It has been suggested that the guidelines address HACCP system principles.
Please provide input on whether good hygiene practices (GHPs) or good
agricultural practices (GAPs) provide adequate control for STEC in a single step or
whether there are applicable CCPs.
A2. In sprout seed production, GHPs or GAPs provide an effective means
of establishing farming practices which minimize potential contamination
by microbiological hazards, including STEC. Providing guidance to producers
on minimizing contamination should be encouraged.
In sprout operations, guidelines that address HACCP system principles,
including prerequisite GHPs are appropriate to reduce the risks associated with
microbiological hazards, including STEC. While we were unable to identify
any CCPs that eliminate microbiological hazards, seed treatment under some
circumstances (i.e. chemical or physical treatments where critical limits can be
set) can be an appropriate CCP to reduce pathogen contamination on seeds for
sprouting, and subsequently reduce public health risk associated with sprouts
(Chen et al., 2018).
Q3. Can JEMRA provide advice on the role of testing of water to control STEC
during sprout seed production? Is testing for STEC warranted and under what
circumstances? What results would indicate a cause for concern? Are there
appropriate indicator organisms that could be used in lieu of or in addition to
testing for STEC? What would be an acceptable level (or levels of concern)?
What should the frequency of water testing be?
A3. JEMRA does not recommend the routine testing of irrigation water for sprout
seed production for the presence of STEC. Information on testing and indicator
organisms were addressed during a JEMRA meeting on the use and reuse of water
in vegetable production (FAO and WHO, 2021a).
Q4. It has been suggested that we include a recommendation for storage under 7 °C.
JEMRA, does the science support this as an appropriate temperature for preventing
growth of STEC in sprouts? Are there other temperatures combined with time that
could apply?

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 A4. Sprouts should be kept at refrigerated temperatures that will minimize
microbial growth for the intended shelf-life of the product. The temperature of
storage areas and transport vehicles should be monitored. Currently there are
limited studies about the minimal temperatures of growth for STEC and other
microbiological hazards for sprouts (Aytac and Gorris, 1994; Tian et al., 2012).
Q5. Question: What is the role of testing sprout seeds and sprouts for STEC and/or
indicator organisms (including acceptable levels of organisms or levels of concern
and frequency of testing)?
A5. Routine STEC testing (or any pathogen testing) of sprout seeds is not
recommended by the experts. Anticipated concentrations and prevalence of
foodborne pathogens present on sprout seeds are low (e.g. Salmonella from seeds
associated with outbreaks were determined to be 13 MPN/kg to 16 MPN/kg and
20 MPN/kg to 100 MPN/kg of dry seeds (Fu et al., 2008; Stewart et al., 2001)).
Pathogenic bacteria are distributed heterogeneously in seed lots (Van Beneden
et al., 1999). The probability for detection of foodborne pathogens in sprout seeds is
estimated to be 0.1 percent, assuming that pathogens are present in one 25 g sample
out of every 1 000 (Montville and Schaffner, 2005). To increase the probability of
detecting any pathogen that may be present in a seed lot, it is necessary to analyse a
large number of samples. EFSA (2011) gives a theoretical example of this problem.
If one seed per kilo is infected, and infected seeds are randomly distributed, then
at least three kilos of seeds need to be analysed in order to ensure that there is a
95-percent chance that the infected seed will be identified (EFSA, 2011).
During sprouting, pathogens of concern, if not eliminated by seed treatment, can
grow to high numbers. Microbial testing of sprout production batch can contribute
to early detection of pathogens and prevent the sale of contaminated sprouts.
Research findings (Fu et al., 2001) highlight that spent sprout irrigation water is a
good indicator of microbial conditions in sprouts and testing spent sprout irrigation
water is an effective method to detect microbial pathogens in a sprout production
batch when using an appropriate sampling plan and testing protocol (FDA, 2017).
While test methods for the detection of Salmonella or E. coli O157:H7 in sprouts or
spent sprout irrigation water are available, the availability of validated test methods
for detection of non-O157:H7 STEC remains limited.

ANNEX 1 – RESPONSE TO THE CODEX COMMITTEE ON FOOD HYGIENE (CCFH) REGARDING SPECIFIC INTERVENTIONS FOR SPROUTS 63
 References
Aytac, S.A. & Gorris, L.G. 1994. Survival of Aeromonas hydrophila and Listeria monocytogenes
on fresh vegetables stored under moderate vacuum. World Journal of Microbiology and
Biotechnology, 10(6): 670–672. https://doi.org/10.1007/BF00327956
Chen, Z., Kim, J. & Jiang, X. 2018. Survival of Escherichia coli O157:H7 and Salmonella
enterica in animal waste-based composts as influenced by compost type, storage
condition and inoculum level. Journal of Applied Microbiology, 124: 1311–1323.
https://doi.org/10.1111/jam.13719
EFSA (European Food Safety Authority). 2011. Scientific opinion of the panel of Biological
Hazards on the risk posed by Shiga toxin-producing Escherichia coli (STEC) and other
pathogenic bacteria in seeds and sprouted seeds. EFSA Journal, 9(11): 2424. https://doi.
org/10.2903/j.efsa.2011.2424
FAO & WHO. 2021a. Safety and quality of water used with fresh fruits and vegetables.
Microbiological Risk Assessment Series No. 37. Rome. FAO. Cited 22 June 2022.
https://www.fao.org/3/cb7678en/cb7678en.pdf
FDA (US Food and Drug Administration). 2017. FY 2014 – 2016 Microbiological sampling
assignment Summary report: Sprouts. Cited 14 June 2022. www.fda.gov/files/food/
published/FY-2014-%E2%80%93-2016-Microbiological-Sampling-Assignment-
Summary-Report-Sprouts-PDF.pdf
Fu, T-J, Reineke, K.F., Chirtel, S. & VanPelt, O.M. 2008. Factors influencing the growth of
Salmonella during sprouting of naturally contaminated alfalfa seeds. Journal of Food
Protection, 71: 888–896. https://doi.org/10.4315/0362-028x-71.5.888
Fu, T., Stewart, D., Reineke, K., Ulaszek, J., Schilesser, J. & Tortorello, M. 2001.
Use of spent irrigation water for microbiological analysis of alfalfa sprouts. Journal of
Food Protection, 64(6): 802–806. https://doi.org/10.4315/0362-028X-64.6.802
Montville, R. & Schaffner, D. 2005. Monte Carlo simulation of pathogen behavior during
the sprout production process. Applied and Environmental Microbiology, 71: 746–753.
https://doi.org/10.1128/AEM.71.2.746-753.2005
Stewart, D.S., Reineke, K.F., Ulaszek, J.M. & Tortorello, M.L. 2001. Growth of Salmonella
during sprouting of alfalfa seeds associated with salmonellosis outbreaks. Journal of
Food Protection, 64: 618–622. https://doi.org/10.4315/0362-028X-64.5.618
Tian, J.Q., Bae, Y.M., Choi, N.Y., Kang, D.H., Heu, S. & Lee, S.Y. 2012. Survival and
growth of foodborne pathogens in minimally processed vegetables at 4 and 15 °C.
Journal of Food Science, 77(1): M48–M50. https://doi.org/10.1111/j.1750-
3841.2011.02457.x
Van Beneden, C.A., Keene, W.E., Strang, R.A., Werker, D.H., King, A.S., Mahon, B.,
Hedberg, K. et al. 1999. Multinational outbreak of Salmonella enterica serotype
Newport infections due to contaminated alfalfa sprouts. JAMA, 281, 158–162.
https://doi.org/10.1001/jama.281.2.158

64 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
 Annex 2

Sprout-associated
foodborne illness outbreaks
and surveillance data
TABLE A2.1 Examples of bacterial contamination rates and their prevalence in sprouts sampled
from the marketplace in three WHO regions for which surveillance data were available.

AMR EUR WPR TOTAL

MICROBIAL PREVAL POS PREVAL POS PREVAL POS PREVAL POS RATE REFERENCES
HAZARD WAVG RATE WAVG RATE WAVG RATE WAVG
Listeria spp. 1% 6/469 0% 0/15 -- -- 1% 6/484 Abadias et al., 2008; FDA 2

Salmonella 0% 0/471 0% 0/15 -- -- 0% 0/486 Abadias et al., 2008; Da Cruz

spp. et al., 2019; FDA 2017

STEC 0%* 0/1383 40% 6/15 -- -- 0% 6/1398 Abadias et al., 2008; CFIA,
2022; FDA 2017

Staphylo- 0% 0/2 -- -- 17% 19/112 0% 19/114 Da Cruz et al., 2019; Seo, Jang
coccus spp. and Moon, 2010

Total 0% 6/2323 13% 6/45 17% 19/112 1% 31/2482

Source: Authors’ elaboration.

* WHO classifications: AMR, Region of the Americas; EUR, European Region; WPR, Western Pacific Region. Preval WAVG, Prevalence as a
weighted average; Pos rate, sample positive rate.

65
TABLE A2.2 Foodborne illness outbreaks associated with the consumption of contaminated sprouts

NO. OF TYPE OF
DATE CAUSATIVE AGENT ILLNESSES SPROUT COUNTRY OF OUTBREAK REFERENCE
REPORTED IMPLICATED

Jan 2020 – E. coli O103 51 Clover sprouts United States of America CDC, 2020
Mar 2020 (multistate)

Nov 2019 – E. coli O103 22 Clover sprouts United States of America FDA, 2020
Dec 2019 (Iowa)

Dec 2017 – Salmonella 10 Sprouts United States of America CDC, 2018

Jan 2018 Montevideo (multistate)

May – July Salmonella 30 Alfalfa sprouts United States of America Beach, 2016
2016 (multistate)

Apr 2016 Salmonella 244 Mung bean Australia Stokes, 2016

Saintpaul sprouts

Jan 2016 E. coli O157 11 Alfalfa sprouts United States of America CDC, 2016b
(Minnesota)

Nov 2015 – Salmonella 13 Alfalfa sprouts United States of America CDC, 2016a
Jan 2016 Muenchen (multistate)

Sep 2014 Salmonella 115 Bean sprouts United States of America CDC, 2015a
Enteritidis (multistate)

Jun – Aug Listeria 5 Mung bean United States of America CDC, 2015b
2014 monocytogenes sprouts (Illinois and Michigan)

May 2014 E. coli O121 19 Raw clover United States of America CDC, 2014a
sprouts (Washington and Idaho)

Jul 2012 Salmonella 19 Sprouts, United States of America CDC, 2022

Cubana unspecified (multistate)

Mar 2012 Listeria 6 Sprouts, United States of America CDC, 2014b

monocytogenes unspecified (multistate)

Dec 2011 – E. coli O26 29 Raw clover United States of America CDC, 2012
Feb 2012 sprouts (multistate)

Aug 2011 Salmonella 7 Sprouts, United States of America CDC, 2022

Agona unspecified (Kansas)

Apr – Jul Salmonella 27 Alfalfa sprouts United States of America CDC, 2011a
2011 Enteritidis and spicy (multistate)
sprouts

May – Jul E. coli O104:H4 4 075 Fenugreek Europe, Canada and United Buchholz et al., 2011; CDC
2011 sprouts States of America 2013

Apr 2011 Salmonella 7 Clover sprouts United States of America CDC, 2022
Muenchen (Michigan)

Dec 2010 – Salmonella 9 Clover sprouts United States of America CDC, 2022
Jan 2011 Newport (Oregon and Washington)

66 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
TABLE A2.2 Foodborne illness outbreaks associated with the consumption of contaminated sprouts. (cont.)

NO. OF TYPE OF
DATE CAUSATIVE AGENT ILLNESSES SPROUT COUNTRY OF OUTBREAK REFERENCE
REPORTED IMPLICATED
Dec 2010 Salmonella 3 Alfalfa sprouts United States of America CDC, 2022
Cubana (multistate)

Nov 2010 – Salmonella 140 Alfalfa sprouts United States of America CDC, 2011b
Feb 2011 serotype I (multistate)
4,[5],12:i:-

Aug - Oct Salmonella 231 Mung bean United Kingdom Cleary et al., 2010
2010 Bareilly sprouts

2010 Salmonella 4 Bean sprouts United Kingdom EFSA, 2011

Kottbus

Mar – Jun Salmonella 44 Alfalfa sprouts United States of America CDC, 2010
2010 Newport (multistate)

Feb 2010 unknown 4 Sprouts, United States of America CDC, 2022

unspecified (Colorado)

Aug 2009 Salmonella 14 Alfalfa sprouts United States of America CDC, 2022
Typhimurium (Michigan)

Jun 2009 Salmonella 42 Alfalfa sprouts Finland Rimhanen-Finne et al., 2011

Bovismorbificans

Apr – Jul Salmonella 20 Onion sprouts Canada Garcia and Heredia, 2020
2009 Cubana and mixed
onion/alfalfa
sprout

Apr 2009 Salmonella 2 Sprouts, United States of America CDC, 2022

Cubana unspecified (Minnesota)

Feb – May Salmonella 256 Alfalfa sprouts United States of America CDC, 2009a, 2009b
2009 Saintpaul (multistate)

Feb 2009 Salmonella 25 Alfalfa sprouts United States of America CDC, 2022
Oranienberg (multistate)

Sep 2008 E. coli O157:NM 21 Alfalfa sprouts; United States of America CDC, 2022
iceberg lettuce, (Colorado)
unspecified

Jul 2008 Salmonella 24 Alfalfa sprouts United States of America CDC, 2022
Typhimurium (multistate)

Mar 2008 Listeria 20 Sprouts, United States of America CDC, 2022

monocytogenes unspecified (multistate)

2008 Staph. aureus 42 Bean sprouts Denmark EFSA, 2011

Jul – Oct Salmonella 45 Alfalfa sprouts Denmark, Norway and Emberland et al., 2007
2007 Weltevreden Finland

ANNEX 2 – SPROUT-ASSOCIATED FOODBORNE ILLNESS OUTBREAKS AND SURVEILLANCE DATA 67

TABLE A2.2 Foodborne illness outbreaks associated with the consumption of contaminated sprouts. (cont.)

NO. OF TYPE OF
DATE CAUSATIVE AGENT ILLNESSES SPROUT COUNTRY OF OUTBREAK REFERENCE
REPORTED IMPLICATED

Jul – Aug Salmonella 44 Alfalfa sprouts Sweden Werner et al., 2007

2007 Stanley

Apr 2007 Salmonella 15 Alfalfa sprouts United States of America CDC, 2022
Mbandaka (multistate)

2006 Salmonella 115 Mung Bean Sweden De Jong, Oberg and

Bareilly and sprouts Svenungsson, 2007
Virchow

Feb 2006 Salmonella 4 Bean sprouts United States of America CDC, 2022
Braenderup (Oregon)

2006 Salmonella 15 Alfalfa sprouts Australia OzFoodNet, 2007

Oranienberg

Nov 2005 Salmonella 125 Alfalfa sprouts Australia ADoH, 2006

Oranienberg

Nov 2005 Salmonella 2 Mung bean United States of America CDC, 2022
Braenderup sprouts (Massachusetts)

Oct – Dec Salmonella spp. 648 Mung bean Canada Ontario Newsroom, 2005
2005 sprouts

Apr 2004 E. coli O157:NM 2 Alfalfa sprouts United States of America CDC, 2022
(Georgia)

Apr 2004 Salmonella 35 Alfalfa sprouts United States of America CDC, 2022
Bovismorbificans (Oregon and Washington)

Nov 2003 Salmonella 26 Alfalfa sprouts United States of America CDC, 2022
Chester (multistate)

Jul 2003 E. coli O157:NM 13 Alfalfa sprouts United States of America Ferguson et al., 2005
(Colorado)

Feb 2003 Salmonella 16 Alfalfa sprouts United States of America CDC, 2022
Saintpaul (multistate)

Feb 2003 E. coli O157:H7 7 Alfalfa sprouts United States of America Ferguson et al., 2005
(Minnesota)

Jan 2003 E. coli O157:H7 20 Alfalfa sprouts United States of America CDC, 2022
(multistate)

Jul 2002 E. coli O157:H7 5 Alfalfa sprouts United States of America CDC, 2022
(California)

2002 Salmonella 13 Mung bean Finland EFSA, 2011

Abony sprouts

Apr 2001 Salmonella 35 Mung bean United States of America CDC, 2022
sprouts (Florida)

68 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
TABLE A2.2 Foodborne illness outbreaks associated with the consumption of contaminated sprouts. (cont.)

NO. OF TYPE OF
DATE CAUSATIVE AGENT ILLNESSES SPROUT COUNTRY OF OUTBREAK REFERENCE
REPORTED IMPLICATED

Feb 2001 Salmonella 32 Alfalfa sprouts United States of America CDC, 2022
Kottbus (multistate)

Jan 2001 Salmonella 22 Mung bean United States of America CDC, 2022; Mohle-Boetani et
Enteritidis sprouts (Hawaii) al., 2001

Feb – Mar Salmonella 84 Mung bean Canada Honish and Nguyen, 2021
2001 Enteritidis sprouts

Oct 2000 unknown 2 Alfalfa sprouts United States of America CDC, 2022
(Florida)

Nov 2000 Salmonella 27 Bean sprouts Netherlands van Duynhoven et al., 2002
Enteritidis phage
type 4b

May 2000 Salmonella 3 Alfalfa sprouts United States of America CDC, 2022
enterica (suspected) (Florida)

2000 Salmonella 75 Mung bean United States of America CDC, 2022

Enteritidis sprouts (multistate)

2000 Salmonella 8 Alfalfa sprouts Canada Harris et al., 2003

Enteritidis

Aug – Sep Salmonella 157 Alfalfa sprouts United States of America Proctor et al., 2001
1999 Muenchen (multistate)

May 1999 Salmonella 36 Clover sprouts United States of America CDC, 2022
Saintpaul (California)

1999 Salmonella spp. 34 Alfalfa sprouts United States of America EFSA, 2011
(multistate)

Jan 1999 Salmonella 83 Alfalfa sprouts United States of America Gill et al., 2003
Mbandaka (multistate)

Jan 1999 Salmonella 112 Clover sprouts United States of America Brooks et al., 2001; Winthrop
Typhimurium (Colorado) et al., 2003

Aug – Sep Salmonella 51 Alfalfa sprouts Canada Stratton et al., 2001

1999 Paratyphi B var java

Jun 1998 E. coli O157:NM 8 Alfalfa sprouts United States of America CDC, 2022; Mohle-Boetani et
(California) al., 2001

May 1998 Salmonella 40 Alfalfa sprouts United States of America CDC, 2022; Mohle-Boetani et
Havana and Cubana (multistate) al., 2001

Jun – Jul E. coli O157:H7 82 Alfalfa sprouts United States of America Breuer et al., 2001; CDC, 1997
1997 (Michigan and Virginia)

ANNEX 2 – SPROUT-ASSOCIATED FOODBORNE ILLNESS OUTBREAKS AND SURVEILLANCE DATA 69

TABLE A2.2 Foodborne illness outbreaks associated with the consumption of contaminated sprouts. (cont.)

NO. OF TYPE OF
DATE CAUSATIVE AGENT ILLNESSES SPROUT COUNTRY OF OUTBREAK REFERENCE
REPORTED IMPLICATED

1997 Salmonella 109 Alfalfa sprouts United States of America Glynn, Patrick and Wuhib,
Infantis and (Kansas and Missouri) 1998; Taormina, Beuchat and
Anatum Slutsker, 1999

Sep 1997 – Salmonella 60 Alfalfa sprouts United States of America Mohle-Boetani et al., 2001
Jul 1998 Senftenberg (California and Nevada)

1997 Salmonella 78 Alfalfa sprouts Canada Sewell and Farber, 2001;

Meleagridis Taormina, Beuchat and
Slutsker, 1999

1997 E. coli O157:H7 126 Radish sprouts Japan Gutierrez, 1997; Taormina,
Beuchat and Slutsker, 1999

May – Jul Salmonella 500 Alfalfa and United States of America Mohle-Boetani et al., 2001
1996 Meleagridis and clover sprouts (California and Nevada)
Montevideo

1996 E. coli O157:H7 6 000 Radish sprouts Japan Watanabe et al., 1999

1996 Salmonella 30 Alfalfa sprouts United States of America Barrett and Chaos, 1996
Stanley (multistate)

1995 –1996 Salmonella >133 Alfalfa sprouts United States of America, Taormina, Beuchat and
Newport Canada and Denmark Slutsker, 1999; Van Beneden
et al., 1999; Wegener et al.,
1997

1995 Salmonella 242 Alfalfa sprouts Finland and United States of Mahon et al. 1997
Stanley America

1994 Salmonella 154 Alfalfa sprouts Denmark WHO, 2003

Newport

1994 Salmonella 595 Alfalfa sprouts Sweden and Finland Pönkä et al., 1995;
Bovismorbificans Puohiniemi, Heiskanen, and
Siitonen, 1997; Taormina,
Beuchat and Slutsker, 1999:

1992 Salmonella enterica 272 Mung bean Finland Mattila et al., 1994
serovar 4, 5, 12:b:- sprouts

Oct 1990 Salmonella 15 Alfalfa sprouts United States of America CDC, 1990
Anatum (Washington)

Oct 1990 unknown 32 Alfalfa sprouts, United States of America CDC, 1990
cucumber, (Washington)
lettuce

1989 Salmonella 31 Cress sprouts United Kingdom Taormina, Beuchat and

Goldcoast Slutsker, 1999; Joce et al.,
1990

70 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
TABLE A2.2 Foodborne illness outbreaks associated with the consumption of contaminated sprouts. (cont.)

NO. OF TYPE OF
DATE CAUSATIVE AGENT ILLNESSES SPROUT COUNTRY OF OUTBREAK REFERENCE
REPORTED IMPLICATED

1989 Listeria 1 Alfalfa sprouts Canada Farber et al., 1990

monocytogenes

1988 Salmonella 148 Mung bean Sweden Nguyen-the and Carlin, 1994
Saintpaul, Havana sprouts
and Muenchen

1988 Salmonella 143 Mung bean United Kingdom O'Mahony et al., 1990
Saintpaul and sprouts
Virchow PT34
(7cases)

1982 Yersinia 16 Bean sprouts United States of America Cover and Aber, 1989
enterocolitica (multistate)

1973 Bacillus cereus 4 Soy, cress, United States of America Portnoy, Goepfert and
mustard (multistate) Harmon, 1976
sprouts

Source: adapted from: Marler, B. 2021. Marler Blog. https://www.marlerblog.com/case-news/barf-blog-a-great-resource-on-why-we-should-

reconsider-sprouts/

ANNEX 2 – SPROUT-ASSOCIATED FOODBORNE ILLNESS OUTBREAKS AND SURVEILLANCE DATA 71

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028X-66.1.13

78 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
FAO/WHO Microbiological Risk
Assessment Series
1 Risk assessments of Salmonella in eggs and broiler chickens: interpretative
summary, 2002

2 Risk assessments of Salmonella in eggs and broiler chickens, 2002

3 Hazard characterization for pathogens in food and water: guidelines, 2003

4 Risk assessment of Listeria monocytogenes in ready-to-eat foods: interpretative

summary, 2004

5 Risk assessment of Listeria monocytogenes in ready-to-eat foods: technical

report, 2004

6 Enterobacter sakazakii and other microorganisms in powdered infant formula:

meeting report, 2004

7 Exposure assessment of microbiological hazards in food: guidelines, 2008

8 Risk assessment of Vibrio vulnificus in raw oysters: interpretative summary and

technical report, 2005

9 Risk assessment of choleragenic Vibrio cholerae O1 and O139 in warm-water

shrimp in international trade: interpretative summary and technical report,
2005

10 Enterobacter sakazakii and Salmonella in powdered infant formula: meeting

report, 2006

11 Risk assessment of Campylobacter spp. in broiler chickens: interpretative

summary, 2008

12 Risk assessment of Campylobacter spp. in broiler chickens: technical report,

2008

13 Viruses in food: scientific advice to support risk management activities: meeting

report, 2008

14 Microbiological hazards in fresh leafy vegetables and herbs: meeting report,

2008

15 Enterobacter sakazakii (Cronobacter spp.) in powdered follow-up formula:

meeting report, 2008

16 Risk assessment of Vibrio parahaemolyticus in seafood: interpretative summary

and technical report, 2011

FAO/WHO MICROBIOLOGICAL RISK ASSESSMENT SERIES 79

 17 Risk characterization of microbiological hazards in food: guidelines, 2009.

18 Enterohaemorrhagic Escherichia coli in raw beef and beef products: approaches

for the provision of scientific advice: meeting report, 2010

19 Salmonella and Campylobacter in chicken meat: meeting report, 2009

20 Risk assessment tools for Vibrio parahaemolyticus and Vibrio vulnificus

associated with seafood: meeting report, 2020

21 Salmonella spp. in bivalve molluscs: risk assessment and meeting report, in

press

22 Selection and application of methods for the detection and enumeration of

human pathogenic halophilic Vibrio spp. in seafood: guidance, 2016

23 Multicriteria-based ranking for risk management of foodborne parasites, 2014

24 Statistical aspects of microbiological criteria related to foods: a risk managers

guide, 2016

25 Risk-based examples and approach for control of Trichinella spp. and Taenia
saginata in meat: meeting report, 2020

26 Ranking of low-moisture foods in support of microbiological risk management:

meeting report and systematic review, 2022

27 Microbiological hazards in spices and dried aromatic herbs: meeting report,

2022

28 Microbial safety of lipid based ready-to-use foods for management of moderate

acute malnutrition and severe acute malnutrition: first meeting report, 2016

29 Microbial safety of lipid based ready-to-use foods for management of moderate

acute malnutrition and severe acute malnutrition: second meeting report, 2021

30 Interventions for the control of non-typhoidal Salmonella spp. in beef and pork:
meeting report and systematic review, 2016

31 Shiga toxin-producing Escherichia coli (STEC) and food: attribution,

characterization and monitoring; report, 2018

32 Attributing illness caused by Shiga toxin-producing Escherichia coli (STEC) to

specific foods: report, 2019

33 Safety and quality of water used in food production and processing: meeting
report, 2019

34 Foodborne antimicrobial resistance: role of the environment, crops and biocides:

meeting report, 2019.

35 Advance in science and risk assessment tools for Vibrio parahaemolyticus and
V. vulnificus associated with seafood: meeting report, 2021.

80 PREVENTION AND CONTROL OF MICROBIOLOGICAL HAZARDS IN FRESH FRUITS AND VEGETABLES

PART 3: SPROUTS
36 Microbiological risk assessment guidance for food: guidance, 2021

37 Safety and quality of water used with fresh fruits and vegetables, 2021

38 Listeria monocytogenes in ready-to-eat (RTE) foods: attribution, characterization

and monitoring: 2022

39 Control measures for Shiga toxin-producing Escherichia coli (STEC) associated

with meat and dairy products: meeting report, 2022

40 Safety and quality of water use and reuse in the production and processing of
dairy products: meeting report, in press

41 Safety and quality of water used in the production and processing of fish and
fishery products: meeting report, in press

42 Prevention and control of microbiological hazards in fresh fruits and vegetables –

Part 1 & 2, general principal: meeting report, in press

43 Prevention and control of microbiological hazards in fresh fruits and vegetables –

Part 3: sprouts: meeting report, 2023

FAO/WHO MICROBIOLOGICAL RISK ASSESSMENT SERIES 81

In 2019, following a request from the Codex Committee on Food Hygiene
(CCFH), the Codex Alimentarius Committee (CAC) approved new work
at its 42nd Session on the development of guidelines for the control of Shiga
toxin-producing Escherichia coli (STEC) in leafy vegetables and in sprouts.
Sprouts have different food safety concerns from other fresh fruits
and vegetables because the conditions under which sprouts are produced
(time, temperature, humidity, pH and nutrients) are ideal for foodborne pathogen
growth. Outbreak investigations have demonstrated that foodborne pathogens
found on sprouts most likely originate from the seed, but the contamination
could also be attributed to the production environment.
This report covers prevention and control measures specific to the primary
production and handling of seed for sprouting, the production of sprouts and
hygienic practices applicable to retail and food services. Recommendations
for proper record-keeping and the establishment of product traceability
programmes that facilitate the identification and investigation of contaminated
seed and sprouts in the event of an illness outbreak or product recall
are also included.

Food Systems and Food Safety - Economic and Social Development

jemra@fao.org
http://www.fao.org/food-safety
Food and Agriculture Organization of the United Nations
Viale delle Terme di Caracalla
00153 Rome, Italy

Department of Nutrition and Food Safety

jemra@who.int
www.who.int/health-topics/food-safety/
World Health Organization
20 Avenue Appia 1211 Geneva 27,
Switzerland