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Yogurt: A Nature’s Wonder for Mankind.

Article in International Journal of Fermented Foods · June 2017

DOI: 10.5958/2321-712X.2017.00006.0

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 Intl. J. Food. Ferment. 6(1): 57-69, June 2017

© 2017 New Delhi Publishers. All rights reserved

DOI: 10.5958/2321-712X.2017.00006.0

Yogurt: A Nature’s Wonder for Mankind

Ramandeep Kaur1, Gurpreet Kaur1, Rima1, Santosh Kumar Mishra*1,
Harsh Panwar1, K.K. Mishra2 and Gurvir Singh Brar1
College of Dairy Science and Technology, GADVASU, Ludhiana, Punjab, India
1

College of Veterinary Science and A.H. (NDVSU), Rewa, M.P., India

2

*Corresponding author: skmishra84@gmail.com

Abstract
Yogurt is a fermented dairy product, having several health benefits. Yogurt starter culture consists of a blend of Streptococcus
thermophilus and Lactobacillus delbrueckii subsp bulgaricus. Today, there are more than 700 yogurt and cheese products found
in Indian cuisine. Consumption of yogurt imparts various health beneficial effects to the host by promoting bone health,
improving diet quality, reducing the incidence of chronic diseases such as obesity and cardio vascular disease. Yogurt also
serves as a vehicle for fortification of several essential nutrients including protein, calcium, potassium, phosphorus and
vitamins B2 and B12. Yogurt properties can be enhanced by the addition or treatment with various additives. Addition
of minerals, herbs or their active components like oils could be an effective strategy to improve functionality of milk and
milk products with respect to the health benefits, food safety and bio preservation. Recent developments in this regard
have been thoroughly discussed.
Keywords: Yoghrt, fortification, functional food, health benefits

INTRODUCTION is a complex gel system its structure includes protein,

polysaccharides and lipids (Marshall, 1993). Yogurt
Yogurt is an ancient fermented dairy product and has
is also considered as the most natural and healthy
been consumed worldwide since the domestication
probiotic. In fact, the beneficial probiotics are the
of mammals (Tamime and Robisons, 2007a). For the
live microorganisms which when taken in adequate
production of Yogurt, the milk is commonly obtained
amount offers various health improving effects.
from several domestic milk producing animals like
Investigations suggest that Yogurt have the ability to
cows, sheep, goat, even yaks, horses, buffalo and
improve digestion, metabolic health and immunity,
camels (Moreno et al., 2013). Yogurt is defined as the
it might cease oncogenic reactions which results in
product of milk which is being manufactured with
reduction of chances of cancer occurrence (Sanders,
or without the addition of some natural derivative of
2000; Sanders, 2007; Holden et al., 2008). Consumption
milk, such as whey concentrates, skim milk powder,
of Yogurt imparts various health beneficial effects to
caseinates or cream with a gel structure that results
the host by promoting bone health, improving diet
from the coagulation of the milk proteins, due to
quality, reducing the incidence of chronic diseases
lactic acid secreted by defined species of bacterial
such as obesity and cardio vascular disease (Donovan
cultures and at the time of consumption these
and Shamir, 2014). The lactic acid producing bacterial
bacteria must be “alive or abundant”. The given
strains that have been used for the culturing of
definition of Yogurt is part of the food legislation of
Yogurt are Lactobacillus bulgaricus and Streptococcus
many countries (Chandan, 2006). Chemically, Yogurt
 Kaur et al.

thermophilus in combination with various optional These days Yogurt is typically milk that has been
dairy ingredients such as cream, milk and skim milk produced by fermentation and acidifying with
(FDA, 2013). Sometimes the other bacterial strains viable and well-defined bacterial strains creating a
such as Lactobacillus acidophilus and Bifidobacterium thickened and flavored product with long shelf life.
bifidus are also added to introduce the more health It contains several essential nutrients and also acts as
beneficial effects. Daily consumption of Yogurt a carrier of fortification of probiotics, fibers, vitamins
results in diminished growth of bacteria which helps and minerals. It is also easily modified according to
in maintaining the micro flora of human gut (Moreno taste by adding sweeteners, fruits and flavors as well
et al., 2013). Yogurt is assumed as healthy food due to as rice, soy or nuts to affect consistency and aroma
its high digestibility and nutrient rich property, also (Fisberg and Rachel, 2015).Yogurt can be defined as
it can be suggested to the persons having diseases the symbiosis of 2 strains of bacteria (S. thermophilus
like irritable bowel movement, inflammatory bowel and L. bulgaricus) in a sterile environment at a very
syndrome and lactose intolerance (Hattingh and low temperature (36˚C - 42˚C) for 3 – 8 hours.
Viljoen, 2001; Mckinley, 2005). Yogurt also serves as a
vehicle for fortification of several essential nutrients YOGURT TYPES
including protein, calcium, potassium, phosphorus Various varieties of Yogurt are now available in the
and vitamins B2 and B12. Trends of fortification of market to meet the nutritional requirements. Yogurt
natural fruits, fruit juice, pulp and dry fruits have is available in various forms, according to texture
been increasing these days (Ghadge et al., 2008). (liquid, set and stirred Yogurt), fat content (high fat,
HISTORY moderate fat, low fat), flavors (natural, fruit, cereal,
chocolate) (Mckinley, 2005). Yogurt can be categorized
Yogurt is also spelled as “Yoghurt ” or “Yoghourt”.
on the basis of its physical and chemical nature,
Yogurt has been a part of the human diet for several
added flavors and post incubational processes.
thousands of years and known by various names
throughout the world (Fisberg and Rachel, 2015). Yogurt consists of various types which are given
Yogurt is also named as katyk (Armenia), dahi below:
(India), zabadi (Egypt), mast (Iran), lebenraib (Saudi
Arabia), laban (Iraq and Lebanon), roba (Sudan), Based on chemical composition
iogurte (Brazil), cuajada (Spain), coalhada (Portugal), According to the fat content, three major varieties
dovga (Azerbaijan), and matsoni (Georgia, Russia of Yogurt are regular, low fat and non-fat Yogurt.
and Japan) (Moreno et al., 2013). It is believed that Regular Yogurt is produced from full fat milk
the name “Yogurt” comes from Turkish word
whereas low fat Yogurt is prepared from low fat or
“Yogurmak” which means to thicken, coagulate or
partially skim milk. For non-fat Yogurt skim milk is
curdle (Fisbergand Rachel, 2015). As the Yogurt is a
used (Weerathilake et al., 2014).
traditional milk product which was incorporated into
the human diet around 10000–5000 BC (Moreno et al., Based on the physical nature
2013). In earlier times, due to the lack of technology
and storage sources, milk spoiled easily, it was so On the basis of physical nature Yogurt can be divided
difficult to preserve for long time (McGee, 2004). So into three categories: solid, semi-solid and fluid.
at that time making Yogurt was only the option to
ˆˆ Set Yogurt: Yogurts that are solid in nature (jelly-
preserve milk from spoilage, other than drying it
like texture) are known as set type Yogurt which is
(Batmanglij, 2007).
incubated and cooled down in the final packaging
Yogurt Today (Dairy Consultant, 2013). The procedure of
manufacturing set Yogurt is explained in Fig. 2.
Today, there are more than 700 Yogurt and cheese
products found in Indian cuisine (Batmanglij, 2007).

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 Yogurt: A Nature’s Wonder for Mankind

ˆˆ Stirred Yogurt: Yogurt in semi-solid state are This category involves two types of Yogurt, Plain/
called as stirred Yogurt. Stirred Yogurts are Natural and flavored Yogurt.
prepared by incubating the mixture and breaking
ˆˆ Plain/Natural Yogurt: This form of Yogurt is the
by stirring prior to cooling and packaging (Dairy
simplest and least adulterated form which is
Consultant, 2013). The texture of stirred Yogurt is
prepared by lactic acid bacterial fermentation of
less firm than set type Yogurt, it seems like very
pasteurized milk in order to produce its texture
thick cream and a little reformation occurs after
and flavor. It does not contain added color and
packaging (Aswal et al., 2012). The procedure of
additives, its plain and unsweetened fermented
manufacturing stirred Yogurt is explained in Fig.
milk product. It contains pure Yogurt taste and
1.
rich amount of calcium among others (Dowden,
2013)
Standardized milk
ˆˆ Flavored Yogurt: Yogurt is present in the form
Homogenization (55-65˚C and 15-20/5MPa)
of various flavors like fruit (apple, blue berry,
Pasteurization of milk (80-85˚C for 30 min) apricot, lemon, black cherry, black currant,
Cooling (40-45˚)
peach, strawberry), vegetables, cereal, chocolate,
caramel, vanilla, etc. These additives itself contain
Addition of starter culture (2 - 3%) 50% sugar whereas people prefers low fat and low
sugar content products. Low or sugar less Yogurt
is commonly sweetened by adding saccharin and
(Set type Yogurt) (Stirred type Yogurt)
aspartame. Flavor is added either at or just prior
Packing Incubation to filing into cups (Aswal et al., 2012).

Incubation Cooling (20 - 25˚C) Others

Chilling and Cooling Stirring ˆˆ Frozen Yogurt: Initially, manufacturing of frozen
Cooling and Pumping Yogurt is somewhat similar to stirred Yogurt.
Inoculation and incubation is carried out in the
same manner as stirred Yogurt. It is prepared
Cold storage and dispatch by freezing while stirring a pasteurized mix.
Cooling is achieved in the same manner as ice-
Figure
Fig. 1:1: Processingof
Processing ofset
set and
and stirred
stirredYogurt
Yogurt cream (Aswal et al., 2012).
ˆˆ Drinking Yogurt: Yogurt in fluid state is known ˆˆ Concentrated Yogurt: This type of Yogurt is
as drinking Yogurt. Drinking Yogurt usually inoculated and fermented in the same way as
go under the process of homogenization to stirred Yogurt. It is followed by breaking of
reduce the particle size which assured the hydro coagulum, and then the Yogurt is concentrated by
colloidal distribution and stabilization of protein boiling off some water under vaccum conditions
suspension (Weerathilake et al., 2014). to reduce the temperature required. Heating of
ˆˆ Processing of set and stirred Yogurt (Lee and low pH Yogurt leads to denaturation of protein
Lucey, 2010) and produces rough and gritty textures (Aswal et
al., 2012).
Based on the flavor of product
ˆˆ Pasteurized Yogurt: These types of Yogurt are
Addition of the flavor to Yogurt makes it more prepared after fermentation by heat treatment
valuable and increase the consumers demand. Flavors with different time-temperature combinations.
can be added either after or before homogenization. These kinds of products are manufactured to

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 Kaur et al.

increase the shelf life of Yogurt or to decrease the and solid non-fat-content (SNF). Bovine milk fat
natural tartness of Yogurt. But the disadvantage content varies from 3.2% - 4.2% (w/w). For skim milk,
of pasteurized Yogurt is destruction of live fat content range from <0.5%, for semi- fat milk, fat
and active cultures during heat treatment content varies from 1.5% - 2% and for full fat milk,
(Weerathilake et al., 2014). fat content is 3.5%. According to the consumer’s
demand, fat content of Yogurt varies from 0.1% - 10%
YOGURT MANUFACTURING PROCESS (Tamime and Robisons, 2007b). In commercial Yogurt
The manufacturing process of simple Yogurt is products milk solid content may varies from 14 -15%
explained in Fig. 2 (Aswal et al., 2012). and the minimum milk solids non-fat content also
varies from 8.2 – 8.6% according to the standards
of various countries (Tamime and Robisons, 1999a).
Liquid milk/Concentrated milk/Milk powder To attain the desired SNF content of milk, the milk
mixture is fortified with milk powder (skimmed
Initial treatment of milk
or full fat), whey protein concentrates or casein
powder which results in increase in firmness and
Milk Standardization and fortification
cohesiveness (Walstra, 2006c). Yogurt mixture should
Homogenization be standardize in such a way that the end product
with not less than 2.7% protein content, milk fat
Heating content should be less than 15%. It is also important
that the titrable acidity of Yogurt should not be less
Cooling than 0.3% expressed as percentage of lactic acid. To
achieve the characteristic properties of Yogurt like
Production of Yogurt texture, mouth feel, viscosity appearance and to
inhibit the whey separation, stabilizers such as pectin
Fig.2:
Fig 2: Processing
Processingofof
Yogurt
Yogurt and gelatin are added to the Yogurt mix (Lee and
Lucey, 2010)
Initial treatment of milk
For all types of Yogurt, the initial step is to prepare Homogenization
the Yogurt mix (milk fat, milk protein, nonfat milk Homogenization is a process of breaking down of fat
solids, sugar, stabilizers, flavors and colors) and the globules into smaller size so that its size becomes less
heat treatment of this mix. Fat content of Yogurt than 1µm and in such a way it is uniformly distributed
may varies, it depends upon the type of milk added throughout the food matrix. Homogenization is
and it can be increased or decreased by adding considered as the most important processing step in
skimmed milk powder, cream or butter fat and whey case of Yogurt having high fat content. This process
concentrates (Weerathilake et al., 2014). restricts the formation of distinct creamy layer on
The Yogurt mix is heat treated for two reasons: first surface of the Yogurt (Chandan and Kilara, 2013).
is to kill pathogens and spoilage microorganisms and Homogenization is carried out using a homogenizer
second is to denature the milk proteins and to carry or viscolizer where the milk is introduced through
out the interactions between them which increase small openings at high pressure which results in
their water-binding capacity and firmness of Yogurt the breaking down of fat globules due to shear
coagulum (Chandan and O’Rell, 2006). forces (Dairy Consultant, 2013). Usually, milk is
homogenized for 10-17minute using pressure of 10-
Milk standardization and fortification 20 MPa in first stage and 5MPa in second stage (Lee
Milk standardization means standardization of fat and Lucey, 2010). Recently, to increase the firmness

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 Yogurt: A Nature’s Wonder for Mankind

and water holding capacity of commercial Yogurt mixture is cooled down to temperature 43-46˚C
than that of conventional, the ultra-high pressure (temperature range for thermophilic bacteria) and the
homogenization has been introduced (Serra M., 2009; 2% (v/v) of Yogurt starter culture bacteria is added
Serra M., 2008) (Dairy Consultant, 2013). Usually the standard Yogurt
culture consists of S. thermophilus and L. dulbrueckii
Pasteurization (Heat treatment) subsp. bulgaricus in 1:1 ratio and the inoculation of
Heat treatment of milk is also one of the most culture takes place in a sealed hygienic stainless
important process of Yogurt manufacturing that steel vessel. In both set and stirred type Yogurt
manufacture, the place of fermentation is different to
affects the microstructure and physical properties
each other. Individual containers and large hygienic
of Yogurt which ensures the safety of product. Heat
stainless steel vats are used for Yogurt manufacturing
treatment helps in the destruction of pathogenic
process for set and stirred type Yogurt respectively.
microorganisms present in milk or Yogurt mixture
Incubation temperature of Yogurt is maintained and
as well as denatures the whey proteins to achieve a
monitored throughout the manufacturing process
better body and texture of product. It also releases
(Weerathilake et al., 2014). When the pH of Yogurt
the compounds in milk that stimulates the growth approaches 5.0, lowering of the activity of ST and
of starter culture bacteria. (Dairy Consultant, 2013; LT initiates which gradually dominates the overall
Lee and Lucey, 2010). Pasteurization is a continuous fermentation process until the desired level of pH
or batch process which involves heating of milk to and acidity reaches. Process is terminated, when
high temperature and holding for determined time the temperature reaches 4˚C, at this temperature
period (Tamime and Robisons, 1999a). Various heat culture remains alive but its activity becomes limited
treatments can be applied on the basis of temperature (Walstra, 2006c; Vedamuthu, 2006). During the
and time which are listed below in Table 1: fermentation process, lactose converts into lactic acid
Inoculation and Fermentation due to the metabolic activity of the lactic acid bacteria
which help in the coagulation of milk proteins and
During this stage Yogurt is formed its texture and the production of volatile compound takes place
flavor are developed (Tamime and Robisons, 2007b; which imparts flavor and aroma (Weerathilake et al.,
Walstra, 2006c). After the pasteurization, the Yogurt 2014).

Table 1: Effect of temperature on Yogurt properties (Sfakianakis and Tzia, 2014)

Heat treatment Temperature & Time Effect on Yogurt

Thermalisation 60-69˚C for 20-30s No significant effect.
Characteristics affected by further
processing (Walstra, 2006a).
Low 63-65˚C for 20 min/ Slight increase in viscosity and firmness
Pasteurization (Tamime and Robisons, 2007a).
70-75˚C for 15-20s
High 85˚C for 20-30 min/ Large increase in viscosity and firmness
Pasteurization (Tamime and Robisons, 2007a).
90-95˚C for 5 min
Sterilization 110˚C for 30 min/ Very large increase in viscosity and
firmness
130˚C for 40s
(Tamime and Robisons, 2007; Walstra,
2006a).
Ultra heat treatment 145˚C for 1-2˚C Medium increase in viscosity and
firmness (Tamime and Robisons, 2007a).

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 Kaur et al.

Cooling even sometime bacterial culture may influence

the vitamin content (Buttriss, 1997)
After the pH of Yogurt reaches to 4.5-4.6 Yogurt is
cooled down to 5˚C in order to stop the fermentation ˆˆ Proteins: Proteins are naturally present in milk
process and further acid development (Tamime in high quality due to its high biological value as
and Robisons, 1999a; Tamime and Robisons, 2007b; well as it contains all the necessary amino acids
Walstra, 2006b).Cooling of Yogurt involves two to maintain good health. Milk proteins available
phases: First phase involves the rapid decrease in in Yogurt contain higher content of proline and
coagulum temperature less to than 10˚C which glycine than in regular milk (Mckinley, 2005).
results in the inhibition of fermentation process leads
ˆˆ Carbohydrates: Lactose is the major carbohydrate
to Yogurt with low viscosity, second phase of cooling
found in Yogurt in comparative to others. In total,
involves the initiation of rapid decrease in coagulum
raw milk contains about 4.6% lactose content.
temperature less than to 20˚C. Then the temperature
However, the amount of lactose is lowered by
of Yogurt lowers down to 5˚C (storage temperature)
20-30% during the fermentation process, as the
with an increased viscosity (Tamime and Robisons,
lactose converts into its simpler form of glucose
2007b; Walstra, 2006b). After manufacturing set-
and galactose due to the metabolic activity of
Yogurts are directly transferred to cold stores or
lactic acid bacteria (USDA, 2001).
chilled in cooling tunnels, whereas coagulum of
stirred-Yogurts are firstly cooled down by agitation ˆˆ Fat content: Fat content of Yogurt depends on the
in order to smoothened the product before filling to fat content of original Yogurt mixture. According
containers (Lee and Lucey, 2010) to the USDA specifications of Yogurt, fat content of
low fat and non-fat Yogurt varies from 0.5-3.25%
COMPOSITION OF YOGURT (USDA, 2001). In case of Yogurt, homogenization
Composition of Yogurt is almost similar to the and fermentation breakdowns the fat into easily
composition of milk from where it is derived but it digestible absorbable fatty acids (Mckinley, 2005).
only varies if other ingredients such as fruit, cereal
Ingredients of Yogurt
or other components are added to the Yogurt.
Yogurt contains protein, carbohydrates, calcium, Yogurt is a mixture of variety of components
phosphorus, vitamins and minerals (Mckinley, 2005). including milk, sweeteners, stabilizers, fruits, flavors
Composition of Yogurt varies according to the variety and bacterial cultures. Milk is the most important
of Yogurt. The average composition of bovine milk ingredient of Yogurt. Selection of the milk depends
includes 3.5% fat, 4.5% lactose, 3.3% protein, 0.7% upon the type of the Yogurt to be manufactured.
mineral matter. For full fat or regular Yogurt whole milk is used,
for low fat partially skimmed milk is preferred and
ˆˆ Vitamins and minerals: Yogurt is a rich source
for fat free Yogurt skim milk is used. To adjust the
of riboflavin (Vitamin B2), thiamin (Vitamin
fat content, cream or butter fat is added whereas to
B1), vitamin B12, folate, niacin, magnesium and
enhance the total solid content of Yogurt mix, skim
zinc (Mckinley, 2005). Yogurt generally contains
milk powder and whey protein concentrate are
Vitamin B1, Vitamin B2 and Vitamin B12.
used. Usually, stabilizers are added to the mixture,
Vitamins have high risk of loss during processing
which improves the texture of Yogurt such as body
of Yogurt because Vitamins are more sensitive to
and firmness as well as prevents whey separation. It
changes in environmental factors than minerals.
also helps in the uniform distribution of ingredients.
Some factors that negatively affect Vitamin
Sweeteners are just added to enhance the flavor and
content are heat treatment, pasteurization,
aroma (Weerathilake et al., 2014) (Table 2).
agitation, ultrafiltration and oxidative conditions

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 Yogurt: A Nature’s Wonder for Mankind

Table 2: Nutritional information of Yogurt (Aswal et al., 2012) which denatures casein micelles resulting in the
formation of coagulated gel and the other is synthesis
Components Value (per100g)
of aromatic compounds (Guler and Park, 2011).
Carbohydrates 4.7 g
Smooth texture, suitable viscosity, good flavor and
Calcium —
low post fermentation acidification are the properties
Energy 257 KJ
of high quality Yogurt product. Recently, it has been
Fat 3.3 g
found that the weak post acidification property is an
Protein 3.5 g important factor for Yogurt starter selection (Donkor
Riboflavin 0.14 mg et al., 2006; Vinderola et al., 2000; De Ancos et al., 2000)
Vitamin 27µg
Lactobacillus delbruikii ssp. bulgaricus (LB) and
YOGURT STARTER CULTURES Streptococcus thermophiles (ST) shows synergic
effect in the milk environment metabolizes lactose
To achieve the desirable characteristics of the product
into lactic acid and results in the reduction of milk
various combinations of starter cultures are used
pH. When together grow in milk, ST grows very
for manufacturing of Yogurt which also provides
fast as LT grows slowly. When the pH of Yogurt
therapeutic benefits to the consumer. Usually
reaches about 5.0, activity of ST lowers whereas LB
manufacturer adds 2–4% Yogurt starter culture
dominates the overall fermentation process until the
according to its activity (Ghadge et al., 2008). Yogurt
target pH reaches and fermentation process ceases
is commonly prepared by fermenting milk using a
(Walstra, 2006c; Vedamuthu, 2006). The growth
symbiotic culture of bacteria Lactobacillus delbruikii
of the symbiotic bacteria enhances changes in the
ssp. bulgaricus (LB) and Streptococcus thermophiles (ST)
native components of milk which are responsible for
under controlled conditions such as temperature
sensory and physiochemical characteristics of Yogurt
and environment (Sanders, 2000; Marshall, 1993).
(Vedamuthu, 2006).
Streptococcus thermophilus subsp. thermophilus (ST)
is only the species of streptococcus genus which is The addition of symbiotic cultures (Bifidobacterium
being used in dairy starter cultures. However Yogurt animalis ssp. lactis) and fortification of whey protein
starter culture may include strains like Lactobacillus concentrate results in a stronger coagulum, increases
acidophilus, Lactobacillus casei, Lactobacillus lactis, firmness and adhesiveness values for the Yogurt
Lactobacillus jugurti, Lactobacillus helveticus, (Hekmat and Reid, 2006).
Bifidobacterium longum, Bifidobacterium bifidus and
Bifidobacterium infantis. ST is a gram positive and STARTER CULTURE SYSTEMS USED FOR
thermophilic bacteria (temp 35-53˚C). It can be also YOGURT PRODUCTION IN DAIRY INDUSTRY
considered as thermo-tolerant bacteria. According In some countries, Lactobacillus bulgaricus is legally
to morphology, its cells are in spherical shape, required in starter cultures for the production of
forming chains, during the early stage of their life as Yogurt, because it provides a typical Yogurt flavor.
it matures, it acquires rod like shape whereas LB is Sometimes Lactobacillus helveticus and Lactobacillus
a rod shaped, gram positive and anaerobic bacteria lactis are sometime mixed with the starter culture
which grows at temperature 40-44˚C. LB also has the Mckinley, 2005).
ability to produce very high amounts of lactic acid
Production of Yogurt on industrial scale includes
bacteria by metabolizing lactose (Walstra et al., 2006c;
common systems of starter culture used for Yogurt in
Vedamuthu, 2006).
dairy industry are:
THE ROLE OF STARTER CULTURE ON YOGURT ˆˆ For the starter culture, it is necessary to produce
These two starter bacteria in Yogurt manufacturing a sterile and conductive environment for growth.
have two major functions one is milk acidification

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 Kaur et al.

ˆˆ To enhance the viscosity and texture, denaturation Due to acid tolerant capability of L. bulgaricus, Yogurt
and coagulation of proteins is required (Gandhi, becomes soft (Pastink et al., 2008). Weak interactions
2006) lead to decreased fermentation rate and unbalanced
growth (Hanemaaijer et al., 2015). To achieve the
ˆˆ Milk or whey based media, corn syrup and
same ratio of two bacteria, the concentration of
molasses, as a basal are used for commercial
inoculum incubation, time and temperature must be
production of Yogurt.
in controlled manner (Hui, 2004). Exopolysaccharides
ˆˆ Some vitamins like vitamin B and specific amino are produced by S .thermophillus which helps in the
acids are used for the optimum growth of starter formation of matrix with the milk proteins resulting
cultures. in the final Yogurt structure (Cheirslip et al., 2003).
ˆˆ To maintain the cell viability cryoprotectants
FACTORS LEADING TO INHIBITION OF
like glycerol, lactose, ascorbate, glutamate and
YOGURT STARTERS
sucrose are used for both frozen and lyophilized
cultures. Yogurt starters are used to fermentation of milk by
producing lactic acid. Yogurt starter performances
ˆˆ pH is controlled by the addition of alkaline
may be inhibited due to the following reasons:
compounds like gaseous NH3, NH4OH, Na2CO3
and KOH (Durso and Hutkins, 2003) ˆˆ Raw milk should be free from pathogenic
microorganism, because starter culture is
ˆˆ Use of direct-vat-set (DVS) reduces the chances of
susceptible to the harmful phages (Josephsen et
phage contamination during Yogurt production
al., 2004).
as well as maintains the strain balance in case of
mixed stain cultures (Surono and Hosono, 2002). ˆˆ Residues of the sanitation chemicals such as
quaternary ammonium compounds, idophors,
THE ASSOCIATIVE GROWTH OF YOGURT hypochlorite and hydrogen peroxide used during
STARTER BACTERIA AFFECTS THE YOGURT cleaning of dairy equipment can also effect the
QUALITY growth of Yogurt culture (Surono et al., 2002).
Protocoorperation is a process in which Yogurt ˆˆ Natural inhibitors secreted in milk such as lactins
bacteria enhance each other’s growth by the and agglutins, but generally destroyed by the
exchange of metabolites (Sieutwerts et al., 2010). heat treatment.
Protocoorperation and symbiosis are the most
ˆˆ Environmental pollutants like insecticides have
important factors of Yogurt bacteria (Streptococcus
also critical effect on Yogurt starter (Teixeira et al.,
thermophillus and Lactobacillus delbrueckii subsp.
1999).
bulgaricus) for their growth. During the production
of Yogurt both the cultures mutually benefits each ˆˆ Both strains have different characteristics,
other (Courtin and Rul, 2003). The combination so their incompatibility cause some changes
of these two strains results in the higher lactic acid like production of acid, flavor, aroma during
and flavor production than from single strain (Hui, fermentation (Robinson et al.,2002).
2004.). The S. thermophillus forms acid much slower
ˆˆ Pasteurization, incubation and cooling
than L. bulgaricus which liberates small peptides
temperature are also significant factors leading to
and amino acids as well enhances the growth of S.
inhibition of Yogurt starters (Gandhi, 2006).
thermophillus (Wong et al., 1983). After three hours of
post incubation, relative amount of bacteria becomes BENEFICIAL EFFECTS AND USES OF LAB
equal. At pH values between 4.2-4.4 as S. thermophilus
is inhibited whereas L. bulgaricus is tolerant to pH Lactic acid bacteria are one of the different species
values as low as 3.5-3.8 (Hattingh and Viljoen, 2001). of bacteria which helps in the production of lactic

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 Yogurt: A Nature’s Wonder for Mankind

acid during fermentation of carbohydrates. These osteoporosis (Park, 2013). Findings suggested that
bacteria are used for the production of Yogurt the Yogurt considered as probiotic, which enhances
and responsible for the taste, colour, and texture digestion, metabolic health, immunity and might
due to the production of various compounds. stop the oncogenic reaction or delays occurrence of
Bacteriocins are the antimicrobial substances which cancer in the body (Sanders, 2000; Sanders, 2007;
are produces by lactic acid bacteria, have the ability Holden. et al., 2008). Yogurt is good source of natural
to cease the pathogens and food spoiling bacteria protein so it is tolerated by lactose mal-absorber. It
(Rattanachikunsopon and Phumkhachorn, 2010). helps in burning fat and act against colon cancer.
Lactic acid bacteria have been known for beneficial Vaginal infection also reduces and strengthens the
effect on human being, such as it helps in prevention collagen in the skin (Aswal et al., 2012).
of various diseases. Sufficient quantity of Yogurt in
daily diet can improve the following diseases (Aswal, TEXTURE OF YOGURT
et al., 2012) like: As Yogurt is the healthiest fermented product,
ˆˆ It prevents from Heliconbeter pylori and strengthens texture is one of the most important components of
the immunity. Yogurt quality. Texture is latin word ‘texura’ (cloth),
used to represent the cross-linking style of wavy
ˆˆ It improves the digestibility especially stomach,
threads. Texture represents all the rheological and
reduce the blood pressure, bad cholesterol, risk
structural attributes (Ramaswamy and Basak, 1991;
of heart attack.
Borwankar, 1992; Foegeding et al., 2011; Fisher and
ˆˆ It protect from vaginal infection, osteoporosis Windhad, 2011). Texture of Yogurt can be affected
and arthritis. by milk composition, dry matter content, heating,
ˆˆ It is good for skin. homogenization, type of bacterial culture, incubation
temperature, cooling, storage time etc. (Kucukcetin,
ˆˆ Protect from colon cancer. 2009). Heat treatment affects the textural properties
ˆˆ Production of antimicrobial substances by lactic of produced Yogurt include characteristics (firmness
acid like organic acids, bacteriocins, diacetyl and cohesiveness), viscosity, flavor, microbial content
and hydrogen peroxide act as preservative and and milk protein. Texture of Yogurt can be enhanced
also cease the growth of harmful putrefactive by adding different ingredients like nonfat dry milk
microorganisms (Noordiana, et al., 2013). or whey (Harvey and McNeil, 1998). Texture and
ˆˆ It is good for lactose mal-absorber, due to removal taste of Yogurt can also be improved by the addition
of toxic or anti-nutritive factors (lactose and of insulin (Kip et al., 2006). By the addition of lacto
galactose) by LAB (Wouters et al., 2002) peroxidase, texture of Yogurt is improved, but its
apparent viscosity decreased (Hirano et al., 1998).
HEALTH BENEFITS OF YOGURT
FORTIFICATION OF MICRONUTRIENTS
Globally, Yogurt is very popular fermented product. THROUGH YOGURT
Nutritionally, Yogurt provides sufficient amount
Recently Yogurt enriched with different micronutrients
of calcium in bio-available form. As Yogurt plays
to meet the human beings requirement. Fortification
a significant role in improving the human health,
is another method to enhance the quality and quantity
consumption and demand for Yogurt has been
of Yogurt with several nutrients such as minerals,
increased (Weerathilake et al., 2014). Yogurt preferred
vitamins and functional ingredients. In addition,
due to abundant nutritional value like essential
fortified Yogurt correct the inadequate nutritional
amino acids, vitamin D, vitamin B6, and vitamin B12,
value as well as prevent diseases due to malnutrition
riboflavin, calcium (Farnworth, 2008; Kolars, 1984).
(Gahruie, et al., 2015).
Yogurt reduces the blood pressure and protect from

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 Kaur et al.

Fortification of minerals products (Renken, 1993; Upreti, 2002; Kazmi, 2007;

Wagner, 2008; Hanson, 2010).
ˆˆ Iron: Fortification of iron can be important to
control the occurrence of deficiency diseases
STORAGE AND PACKAGING CONDITION
like anemia, alter mental development, poor
immunity and impair cognitive score in kids Packaging
and leads to poor pregnancy (Gaucheron, 2001;
Martinez et al., 2002). As Iron is pro-oxidant so, it Packaging plays an important role. It provide
initiates lipid oxidation and iron compounds does protection from the external force and also attractive,
not affects the nutritional and sensory properties convenient for distribution. A good oxygen barrier
(taste, flavor) of food during processing (El- will help the product from oxidation (Mattila-
Kholy, et al.,2011). Sandholm et al., 2002; Vasiljevic and Shah, 2008). For
th packaging of Yogurt, different types of packaging
ˆˆ Calcium: Yogurt is fortified with tri-calcium material used (Brody, 2006; Nilsen et al., 2002; Tamime
citrate which contains 1 g/L of calcium (Gerhart, and Robinson, 1999b). Commonly, packaging
2013). Deficiency of calcium results in fracture of material used is thermoformed HIPS (High Impact
bones in adult female and also in males. It is right Polystyrene) in the form of small cups or larger tubs
way to increase the level of calcium in Yogurt. with either an aluminum foil/plastic laminate or a
Moreover, organoleptic properties are not paper/plastic laminate heat-seal lid or closure. These
affected by calcium fortification and also reduce containers may be packed in form-fill-seal machines
the risk of bone fracture (Ocak and Ranjendram, or be delivered performed from packaging materials
2013). suppliers. A pigment (TiO2) is added to HIPS to
ˆˆ Magnesium and zinc: These minerals can be enhance the appearance or protect the package from
important and effective on individual health light. This also helps in heating and softening the
as calcium. Tri-magnesium and zinc citrate HIPS sheet for thermoforming when radiant heating
can be used to fortify dairy products (Gerhart, is used (Robertson, 2006). Rectangular paperboard
2013). Deficiency of magnesium causes serious cartons or cups (with or without an aluminum foil
biochemical and symptomatic changes and zinc layer), glass containers, PP (polypropylene), HDPE
deficiency cause growth retardation, behavioral (high density polyethylene) containers are also
disturbances, night blindness, delayed healing popular. PET (polyethylene terephthalate), PVC
of wounds and impaired taste (King and Keen, (polyvinyl chloride), PVdC (Polyvinylidene chloride
1994). copolymer), PLA (polylactate), ceramic containers
have also been used in many markets for some
Fortification of vitamins specialty products (Faderiksen et al., 2003, Tamime
and Robnison, 1999b).
Vitamins are compounds, which play significant role
as cofactors in the human body. Diseases occurred
Storage
due to the deficiency of vitamin D are childhood
rickets, osteoporosis and osteomalacia. It has been Cow milk, dried milk, and soy milk Yogurt could
found that the risk of developing cancer, osteoporotic be stored for two weeks in refrigerator or freezer
fractures and autoimmune diseases also increased and for a week or less at room temperature without
due to the vitamin D deficiency (Holick, 2002). It any effects on the physio-chemical, microbial and
might also reason for type 1 diabetes, hypertension, sensory properties (Muhammad et al., 2009). After
multiple sclerosis and various other cancers (Holick, lyophilization and gamma irradiation treatment
2004). Different researches have been conducted on Yogurt is packed in polymer packing – three-
the stability of vitamin D in milk and other dairy layer aluminum folio, under vacuum and stored at
temperature 0°C - 5°C (Ivanova et al., 2011)

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 Yogurt: A Nature’s Wonder for Mankind

REFERENCES Dowden, A., 2013. The Good Yogurt Guide. Daily Mail,
[online] 4 December. Available at:<http://www.dailymail.
Aswal, P., Shukla, A. and Priyadarshi, S. 2012. Yogurt: co.uk/health/article-19005/The-good-Yogurt-guide.html>
Preparation, characteristics and recent advancements; [Accessed 4 December 2013]
Cibtech Journal of Bio-Protocols, 1(2): 2319–3840.
El-Kholy, A.M., Osman, M., Gouda, A. and Ghareeb, W.A.
Batmanglij, N.A. 2007. Taste of Persia. An introduction to 2011. Fortification of Yoghurt with Iron. World Journal of
Persian cooking, Mage Publishers, Washington, DC. Dairy & food Sciences, 6(2): 159-165.
Borwankar, R.P. 1992. Food Texture and Rheology: A Tutorial Farnworth, E.R. 2008. Handbook of fermented functional
Review. Journal of Food Engineering, 16: 1–16. foods. Taylor and Francis, LLC: Boca Raton, FL, UK. p. 114.
Brody, A.L. 2006. Fermented Dairy Packaging Materials. In: FDA. 2013. Yogurt. 21 CFR 131.200, Code of Federal
Manufacturing Yogurt and Fermented Milks. Chandan Regulations. U. S. Dept. of Health and Human Services,
R.C., Kilara A., Hui Y.H., Ed. Oxford: Blackwell Publishing, Washington, DC.
England.
Fisberg, M. and Rachel, M. 2015. History of Yogurt and Current
Buttriss, J. 1997. Nutritional Properties of Fermented Milk Patterns of Consumption. Nutrition Reviews, 73(S1): 4–7.
Products. International Journal of Dairy Technology, 50: 21–7.
Fisher, P. and Windhad, E.J. 2011. Rheology of Food Materials.
Chandan, R.C. 2006. Chapter 1 History and Consumption Current Opinion in Colloid and Interface Science, 16: 36–40.
Trends. In: Manufacturing Yogurt and Fermented Milks.
Chandan R.C., Ed. Blackwell Publishing: Ames, IA, USA, Foegeding, E.A., Daubert, C.R., Drake, M.A., Essick, G.,
p. 3–17. Trulsson, M., Vinyard, C.J. et al. 2011. A Comprehensive
Approach to Understanding Textural Properties of Semi-
Chandan R.C. and Kilara A. 2013. Manufacturing Yogurt and and Soft-solid Foods. Journal of Texture Studies, 42: 103–129.
Fermented Milks. Wiley Blackwell Publishers, USA.
Frederiksen, C.S., Haugaard, V.K., Poll, L. and Becker, E.M.
Chandan, R.C. and O’Rell, K.R. 2006. Principles of Yogurt 2003. Light-Induced Quality Changes in Plain Yoghurt
Processing. In: Manufacturing Yogurt and Fermented Packed in Polylactate and Polystyrene. European Food
Milks. Chandan R.C., Kilara A., Hui Y.H., Ed. Oxford, Research and Technology, 217: 61–69.
Blackwell Publishing, England, pp. 195–197.
Gahruie, H.H., Mohammad, H.E., Gholamreza, M. and
Cheirsilp, B.H., Shoji, H., Shimizu, H. and Shioya S. 2003. Mohammad, A.H. 2015. Scientific and Technical Aspects
Interactions between Lactobacillus kefiranofaciens and of Yoghurt Fortification: A Review. Food Science and Human
Saccharomyces cerevisiae in Mixed Culture for Kefiran Wellness, 4: 1-8.
Production. Journal of Bioscience and Bioengineering, 96: 279-
284. Gandhi, D.N. 2006. Food and Industrial Microbiology.
Microbiology of Fermented Dairy Product. Dairy
Courtin, P. and Rul, F. 2003. Interactions between Microbiology Division. National Dairy Research
Microorganisms in a Simple Ecosystem: Yogurt Bacteria as Institute, Karnal. http://nsdl.niscair.res.in/jspui/
a Study Model. EDP Sciences, 84: 125-134. bitstream/123456789/117/1/dairymicrobiology.pdf
Dairy Consultant, 2013. Dairy Science Information. [online] Gaucheron, F. 2001. Iron Fortification in Dairy Industry. Trends
Available at: <http://www. dairyconsultant.co.uk/si-Yogurt. in Food Science and Technology, 11(11): 403-9.
php#> [Accessed 5 December 2013]
Gerhart, M. and Schottenheimer, M. 2013. Mineral Fortification
De Ancos, B., Cano, M.P. and Gomez, R. 2000. Characteristics in Dairy. Wellness foods, Europe. p. 30.
of Stirred Low-Fat Yogurt as Affected by High Pressure.
International Journal of Dairy Technology, 10: 105-111. Ghadge, P.N., Prasad, K. and Kadam, P.S. 2008. Effect
of Fortification on the Physio- Chemical and Sensory
Donkor, O.N., Henriksson, A. Vasiljevic, T. and Shah, N.P. Properties of Buffalo Milk Yogurt. Electronic Journal of
2006. Effect of Acidification on the Activity of Probiotics in Environmental, Agriculture and Food Chemistry, 7: 2890-2899.
Yogurt During Cold Storage. International Journal of Dairy
Technology, 16: 1181-1189. Guler, Z. and Park, Y.W. 2011. Characteristics of Physico-
Chemical Properties, Volatile Compounds and Free Fatty
Donovan, S.M. and Shamir, R. 2014. Introduction to the Acid Profiles of Commercial Set-Type Turkish Yogurts.
Yogurt in Nutrition Initiative and the First Global Summit Journal of Animal Sciences, 1: 1-9.
on the Health Effects of Yogurt. American Journal of Clinical
Nutrition, 99: 1209S–11S. Hanson, A.L. and Metzger, L.E. 2010. Evalution of Increased
Vitamin D Fortification in High-Temperature, Short-Time
Durso, L. and Hutkins, R. 2003. “Starter Cultures”, in Processed 2% Milk, UHT-Processed 2% Fat Chocolate Milk,
Encyclopedia of Food Science and Nutrition, B. Caballero, and Low-Fat Strawberry Yoghurt. Journal of Dairy Science,
L. Trugo, P. Finglas, Ed. Academic Press, United Kingdom, 93: 801-807.
pp. 5583-5593.

Print ISSN: 2319-3549 67 Online ISSN: 2321-712X

 Kaur et al.

Hanemaaijer, M., Roling, W.F., Olivier, B.G., Khandelwal, R.A., Kucukcetin, A., Weidendorfer, K. and Hinrichs, J. 2009.
Teusink, B. and Bruggeman, F.J. 2015. Systems Modeling Graininess and Roughness of Stirred Yoghurt as Influenced
Approaches for Microbial Community Studies: From by Processing. International Dairy Journal, 19: 50-55.
Metagenomics to Inference of the Community Structure. Lee, W.J. and Lucey, J.A. 2010. Formation and Physical
Frontiers in Microbiology, 6: 213. Properties of Yogurt. Asian-Australian Journal of Animal
Harvey, L.M. and McNeil, B. 1998. Thickeners of Microbial Science, 23(9): 1127-1130.
Origin. B.J.B. Wood; Microbiology of fermented foods, 1: 148- Marshall, V.M. 1993. Starter Cultures for Milk Fermentation
171. and their Characteristics. International Journal Dairy
Hattingh, L.A. and Viljoen, B.C. 2001. Yogurt as Probiotic Technology, 46: 49-56.
Carrier Food. International Dairy Journal, 11(1): 1-17. Martinez, N.N., Camacho, M.M., Martinez, L.J., Martinez, M.J.
Hekmat, S. and Reid, G. 2006. Sensory Properties of Probiotic and Fito, P. 2002. Iron Deficiency and Iron Fortified Foods-
Yogurt is Comparable to Standard Yogurt. Nutrition A Review. Food Research International, 35: 225-31.
Research, 26: 163–166. Mattila, S.T., Myllarinen, P., Crittenden, R., Mogensen, G.,
Hirano, R., Hirano, M., Oooka, M., Dosako, S., Nakajima, I. Fonden, R. and Saarela, M. 2002. Technological Challenges
and Igoshi, K. 1998. Lactoperoxidase Effects on Rheological For Future Probiotic Foods. International Dairy Journal, 12:
Properties of Yogurt. Journal of Food Science, 63(1): 35-38. 173–182.
Holden, J.M., Lemar, L.E. and Exler, J. 2008. Vitamin D in McGee, H. 2004. Fresh Fermented Milks and Creams. In:
Foods: Development of the US Department of Agriculture Dorfman, P., Greene, J. and McGee, A., Ed. Food and
Database. American J. Clinical Nutrition, 87: 1092S-6S. Cooking: The Science and Lore of the Kitchen. New York:
Holick, M.F. 2002. Vitamin D: The Underappreciated Scribner. p. 44–51.
D-lightful Harmone that is Important for Skeletal and Mckinley, M.C. 2005. The Nutrition and Health Benefits of
Cellular Health. Current Opinion in Endocrinology Diabeties Yogurt. International Journal of Dairy Technology, 58(1): 1-12.
and Obesity, 9: 87-98. Moreno, A.L.A., Cervera, R.P., Ortega, A.R.M., et al. 2013.
Holick, M.F. 2004. Vitamin D: Importance in the Prevention of Scientific Evidence about the Role of Yogurt and Other
Cancers, Type 1 Diabetes, Heart Disease, and Osteoporosis. Fermented Milks in the Healthy Diet for the Spanish
American Journal of Clinical Nutrition, 79: 362-371. Population (Spanish) Nutricion Hospitalaria, 28: 2039–2089.
Hui, Y.H. 2004. Handbook of Food and Beverage Fermentation Muhammad, B.F., Abubakar, M.M. and Adegbola T.A. 2009.
Technology. Marcel Dekker, New York. Effect of Period and Condition of Storage on Properties
Ivanova, S., Miteva, D., Nacheva, I. and Tsvetkov, T. 2011. of Yoghurt Produced from Cow Milk Soymilk Material.
Assessment of the Effect of the Technological Processing Research Journal of Dairy Sciences, 3(2): 18-24.
and the Storage Term on the Fatty Acid Composition of Nilsen, K.O., Evavold, S. and Solgaard, R.T. 2002. Influence of
Buffalo Yoghurt. Bulgarian Journal of Agriculture Science, Packaging Materials on the Keeping Quality of Fermented
17(3): 269-276. Milk. In: Fermented Milk—Proceedings of the IDF Seminar
Salminen, S., Wright, A.V. Ouwehand, A. 2004. “Bacteriaphage on Aroma and Texture of Fermented Milk, International
and Antiphage Mechanisms of Lactic Acid Bacteria” in Dairy Federation, p. 215–224.
Lactic Acid Bacteria: Microbiological and Functional Noordiana, N., Fatimah, A.B. and Mun, A.S. 2013. Antibacterial
Aspects by Salminen, S., Wright, A.V. Ouwehand, A., Ed. Agents Produced by Lactic Acid Bacteria Isolated from
Marcel Dekker Inc., New York. p. 295-350. Threadfin Salmon and Grass Shrimp. Journal of Animal
Kazmi, S.A., Vieth, R. and Roussseau, D. 2007. Vitamin Science, 2(7): 19-1905.
D3 Fortification and Quantifiction in Processed Dairy Ocak, E. and Rajendram, R. 2013. Fortification of Milk with
Products. International Dairy Journal, 17: 753-759. Mineral Elements. V.R. Preedy et al. Ed. Handbook of Food
Kings, J.C., Keen, C.L., Shils, M.E., Olson, J.A. and Shike, M. Fortification and Health, Springer, New York.
1994. Zinc in: Modern Nutrition in Health and Disease. Park, K.M. and Cifelli, C.J. 2013. Dairy and Blood Pressure: A
M. E. Shils, J. A. Olson and M. Shike, Ed. Lea & Febiger, Fresh Look at the Evidence. Nutrition Reviews, 71: 149-157.
Philadelphia. 8: 214-230. Pastink, M.I., Sieuwerts, S., De Bok, F.A.M., Janssen, P.W.M.,
Kip, P., Meyer, D. and Jellema, R.H. 2006. Insulins Improve Teusink, B., Hylckama, V.J.E.T., et al. 2008. Genomics and
Sensoric and Textural Properties of Low Fat Yoghurt. High-Throughput Screening Approaches for Optimal
International Dairy Journal, 16: 1098-1103. Flavour Production in Dairy Fermentation. International
Kolars, J.C., Levitt, M.D., Aouji, M. and Savaiano, D.A. 1984. Dairy Journal, 1(8): 781-9.
Yogurt--An Auto Digesting Source of Lactose. New England Ramaswamy, H.S. and Basak, S. 1991. Rheology of Stirred
Journal of Medicine, 310: 1-3. Yogurts. Journal of Texture Studies, 22: 231–241.

Print ISSN: 2319-3549 68 Online ISSN: 2321-712X

 Yogurt: A Nature’s Wonder for Mankind

Rattanachaikunsopon, P. and Phumkhachorn, P. 2010. Lactic Tamime, A.Y. and Robisons, R.K. 2007b. Chapter 2 Backround
Acid Bacteria: Their Antimicrobial Compound and Their to Manufacturing Practice. In Tamime and Robinson’s
Uses in the Production. Annals of the Biological Research, Yogurt: Science and Technology, 3rd edn., Woodhead
1(4): 218-228. Publishing, Cambridge, UK, pp. 11–118.
Renken, S.A. and Warthesen, J.J. 1993. Vitamin D Stability in Teixeira, P.C.M., 1999. “Lactobacillus bulgaricus” in Enyclopedia
Milk. Journal of food science, 58: 552-555. of Food Microbiology, edited by C. Batt, P. Patel, R.
Robertson, G.L. 2006. Structure and Related Properties of Robinson, Academic Press, United Kingdom. p. 1136-1144.
Plastic Polymers. In: Food Packaging Principles and Upreti, P., Mistry, V. and Warthesen, J. 2002. Estimation and
Practice, 2nd edn. Boca Raton, Florida: CRC Press. p. 9–42. Fortification of Vitamin D3 in Pasteurized Process Cheese.
Robinson, R.K., 2002. “Yoghurt, Role of Starter Cultures”, in Journal of Dairy Science, 85: 3173-3181.
Encyclopedia of Dairy Science, H. Roginski, J. Fuquay, P. USDA. 2001. USDA Specifications for Yogurt, Nonfat Yogurt
Fox, Ed. Academic Press, United Kingdom, pp. 1059-1063. and Low fat Yogurt. Dairy Programs. Agricultural
Sanders, M.E. 2000. Considerations For Use of Probiotic Marketing Services. United States Department of
Bacteria to Modulate Human Health. Journal of Nutrition Agriculture: Washington, DC.
education, 130: 384S-390S. Vasiljevic, T. and Shah, N.P. 2008. Cultured Milk and Yogurt.
Sanders, M.E. 2007. Probiotics, Strains Matter. Functional In: Dairy Processing and Quality Assurance. Chandan R.C,
Foods & Nutraceuticals Magazine. Food Science, p. 36–41. Kilara A., Shah N.P. Ed. Ames, Iowa: Wiley-Blackwell, pp.
219–251.
Serra, M., Trujillo, A.J., Jaramillo, P.D., Guamis, B. and Ferragut,
V. 2008. Ultra-High Pressure Homogenization-Induced Vedamuthu, E.R. 2006. Chapter 6 Starter cultures for Yogurt and
Changes in Skim Milk: Impact on Acid Coagulation fermented milks. In Manufacturing Yogurt and Fermented
Properties. Journal of Dairy Research, 75(1): 69. Milks; Chandan, R.C., Ed.; Blackwell Publishing: Ames, IA,
USA, p. 89–117.
Serra, M., Trujillo, A.J., Guamis, B. and Ferragut, V. 2009.
Evaluation of Physical Properties during Storage of Set Vinderola, C.G., Bailo, N. and Reinhemier, J.A. 2000. Survival
and Stirred Yogurts Made From Ultra-High Pressure of Probiotic Microflora in Argentinian Yogurts during
Homogenization-Treated Milk. Food Hydrocolloids, 23(1): Refrigerated Storage. Food Research International, 33: 97-102.
82-91. Walstra, P., Wouters, J.T.M. and Geurts, T.J. 2006a. Chapter 7
Sfakianakis, P. and Tzia, C. 2014. Conventional and Innovative Heat Treatment. In Dairy Science and Technology; Taylor
Processing of Milk for Yogurt Manufacture, Development & Francis Group, LLC: Boca Raton, FL, USA, pp. 225–272.
of Texture and Flavor: A Review. Foods, 3:176-193. Walstra, P., Wouters, J.T.M. and Geurts, T.J. 2006b. Chapter 11
Siddiquil, A.A. and Chowdhury, M.N.A. 2013. Shelf Life Study Cooling and freezing. In Dairy Science and Technology;
of Yogurt by Using Different Concentration of Lactobacillus Taylor & Francis Group, LLC: Boca Raton, FL, USA, p.
acidophilus. Journal of SUB, 4(2): 43-54. 297–307.
Sieuwerts, S., Molenaar, D., van Hijum, S.A., Beerthuyzen, Walstra, P. Wouters, J.T.M. and Geurts, T.J. 2006c. Chapter 22
M., Stevens, M.J., Janssen, P.W. et al. 2010. Mixed-Culture Fermented Milks. In Dairy Science and Technology; Taylor
Transcriptome Analysis Reveals the Molecular Basis of & Francis Group, LLC: Boca Raton, FL, USA, pp. 551–573.
Mixed-Culture Growth in Streptococcus thermophilus and Wagner, D., Roussseau, D., Sidhom, G.R., Pouliot, M., Audet, P.
Lactobacillus bulgaricus. Applied environment microbiology, and Vieth, R. 2008. Vitamins D3 Fortication, Quantification
76(23): 7775-84. and Long Term Stability in Cheddar and Low-Fat Cheeses.
Surono, I. and Hosono, A. 2002. “Starter Cultures” in Journal of Agriculture and Food Chemistry, 56: 7964-7969.
Encyclopedia of Dairy Science, H. oginski, J. Fuquay, P. Weerathilake, W.A.D.V., Rasika, D.M.D., Ruwanmali,
Fox, Ed. Academic Press, United Kingdom, p. 1023-1028. J.K.U. and Munasinghe, M.A.D.D. 2014. The Evolution,
Tamime, A.Y. and Robinson, R.K. 1999a. Yogurt: Science and Processing, Varieties and Health Benefits of Yogurt,
Technology. Woodhead Pub Limited, Cambridge, UK. International Journal of Scientific and Research Publications,
4(4): 2250-3153.
Tamime, A.Y. and Robinson, R.K. 1999b. Packaging. In:
Yoghurt Science and Technology. Tamine A.K., Robinson Wong, N.P., Mcdonough, F.E., and Hitchins, A.D. 1983.
R.K., Ed. 2nd edn., Woodhead Publishing, Cambridge, UK. Contribution of Streptococcus thermophilus to Growth-
p. 90–103. Stimulating Effect of Yogurt on Rats. Journal of Dairy
Science, 66: 3.
Tamime, A.Y. and Robisons, R.K. 2007a. Chapter 1 Historical
Background. In Tamime and Robinson’s Yogurt: Science and Wouters, J.T.M., Ayad, E.H.E., Hugenhltz, J. and Smit, G.
Technology, 3rd edn., Woodhead Publishing: Cambridge, 2002. Microbes from the Raw Milk for Fermented Dairy
UK. pp. 1–10. Products. International Dairy Journal, 12: 91-109.

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