GENU® Pectin

GENU® Pectin Book

www.cpkelco.com
 ®
GENU PECTIN
GENERAL DESCRIPTION

CP Kelco ApS
Ved Banen 16 • 4623 Lille Skensved
Denmark
Telephone: +45 56 16 56 16
TeleFax: +45 56 16 94 46
 Index
GENERAL DESCRIPTION OF PECTIN

Definition 3
Food Regulatory Status 3
Raw Material 3
Manufacturing Process 4
Structure 5

GENERAL PROPERTIES OF PECTIN

Solubility 7
Dissolution with high-speed mixer 7
Preblending with sugar 7
Dispersing in concentrated sugar solution 8
Viscosity 8
Reactions 8
Stability in solution 8
Reactions with other electrically charged hydrocolloids 9
Gelling Mechanism 9
Temperature 10
Types of pectin 11
pH 12
Sugar and other solutes 12
Calcium ions 12

COMMERCIAL PECTINS

Powder Characteristics and Storage Stability 13

Stability 14
Standardization 14
High ester pectin 14
Low ester pectin 15
Quality Control 15
Purity determination 15
Calcium reactivity 16

APPLICATIONS

Food Applications 17
Jams and jellies 17
Fruit preparations for yoghurt 18
Fruit drink concentrates 18
Fruit juice 18
Fruit/milk desserts 18
Fermented and directly acidified dairy products 19
Gelled milk products 19
Confectionery products 19
Pharmaceutical Applications 19

GENU Pectins 20
Additional Technical Literature 20
Because we cannot anticipate or control the many different con- ions and shall at no time form the basis - totally or partially - of a
ditions under which this information and our products may be liabilityon our part. For the same reason, the products are sold
used, we do not guarantee the applicability or the accuracy of without warranty, express or implied. Statements concerning the
this information or the suitability of our products in any individual possible use of our products are not intended as
situation. Any information or instruction pertaining to the use of recommendations to use our products in the infringement of any
our products shall be regarded solely as non-binding suggest- patent.

08.2001
 General Description of Pectin
DEFINITION
Pectin is a purified carbohydrate product obtained by aqueous extraction of appropriate
edible plant material - usually citrus fruits or apples.

All green land plants contain pectin substances which in combination with cellulose are
responsible for the structural properties of fruits and vegetables. Pectin consists mainly of
galacturonic acid and galacturonic acid methyl ester units forming linear polysaccharide
chains and is normally classified according to its degree of esterification.

In high (methyl) ester or HM-pectin a relatively high portion of the carboxyl groups occur as
methyl esters, and the remaining carboxylic acid groups in the form of the free acid or as its
ammonium, potassium, calcium or sodium salts; its useful properties may vary with the
degree of esterification and with the degree of polymerization. Pectin in which less than
50% of the carboxyl acid units occur as the methyl ester is normally referred to as low
(methyl) ester or LM-pectin. In general, low ester pectin is obtained from high ester pectin
by a treatment at mild acidic or alkaline conditions.

Amidated pectin is obtained from high ester pectin when ammonia is used in the alkaline
deesterification process. In this type of pectin some of the remaining carboxylic acid groups
have been transformed into the acid amide. The useful properties of amidated pectin may
vary with the proportion of ester and amide units and with the degree of polymerization.
Commercial pectin is normally blended with sugars for standardization purposes, and some
types may contain suitable food grade buffer salts required for control of pH and desirable
setting characteristics.

FOOD REGULATORY STATUS

As a constituent of all land plants, pectin has been part of the human diet from the origin of
man. Pectin has been evaluated and cleared toxicologically by JECFA (the Joint FAO/
WHO Expert Committee on Food Additives). A group ADI „not specified“ was established
for pectins and amidated pectins, meaning that from the toxicological point of view there
are no limitations on the use of pectins and amidated pectins.

In most countries, food legislative authorities recognize pectin as a valuable and harmless
food additive. If regulated, permitted use levels are generally in accordance with „Good
Manufacturing Practice.“

RAW MATERIAL
The amount and composition of pectin contained in plant material vary from one variety of
plant to another. Mainly citrus fruits and apples are used as raw materials for the manufacture
of commercial pectins.

Citrus pectins are derived from the peel of lemon and lime and, to a minor extent, orange
and grape fruit. Citrus peel is a by-product from juice and oil pressing and contains a high
proportion of pectin with desirable properties.
 Parts of the citrus fruits used in the pectin manufacture.

Apple pomace, the residue from apple juice pressing, is the raw material for commercial
apple pectins. These are normally darker in colour (brownish shade) than citrus pectins,
but in functional properties there are no essential differences.

MANUFACTURING PROCESS
Pectin manufacture comprises three to four essential steps:

1. Extraction from the plant material.

2. Purification of the liquid extract.
3. Isolation of pectin from the solution, and - if low ester (LM) pectin is the end
product desired:
4. De-esterification of the high ester (HM) pectin.

The extraction of pectin is made with hot acidified water. Quantity and quality of pectin from
the specific raw material to a great extent depend on proper selection and control of
extraction conditions. The extract is clarified by centrifugation and a number of filtrations,
the last step being a polishing filtration to ensure complete transparency in application.

Precipitation of pectin from solution may either be done with alcohol from a concentrated
(2-4%) pectin solution or with an aluminium salt from a diluted (0.3-0.5%) pectin solution.
When pectin is isolated as aluminium pectinate, precipitation must be followed by washing
with acidified alcohol to convert the aluminium pectinate to the acid form and subsequent
neutralization with slightly alkaline alcohol.

The pectin obtained by these processes is high ester pectin. This type of pectin only forms
gels above a soluble solids of approx. 55%.

Low ester pectin - which forms gels in the presence of calcium ions irrespective of soluble
solids - is obtained by a controlled de-esterification of high ester pectin at either acidic or
alkaline conditions. If ammonia is used to de-esterify the pectin, some amide groups are
introduced into the molecule and a so-called amidated pectin is obtained.
The manufacturing processes are in principle simple unit operations, but much know-how
is accumulated in the practical execution of the processes. The flow chart below gives a
general description of the process used by CP Kelco ApS.

vv v
Citrus peel Extraction Ammonia
Peel waste
v
Water (cattle feed)
Filtration

v
Acid v
Concentration
v v

v
Alcohol Precipitation Deesteriufiucation
v

v
Alcohol
v recovery v

v
Drying Drying
v v
Milling Milling
v v
Sugar Blending Sugar Blending
v

v
v v
Standardized Standardized
H-pectin LM-pectin

Pectin manufacture (alcohol precipitated product)

STRUCTURE
Pectin is an essentially linear polysaccharide containing from a few hundred to about 1000
saccharide units in a chain-like configuration; this corresponds to average molecular weights
from about 50,000 to 150,000.

D-galacturonic acid is the principal constituent of the pectin molecule, but some neutral
sugars are also commonly present in pectin. The D-galacturonic acid units are linked together
by ß-1.4 glycosidic linkages.
The polygalacturonic acid is partly esterified with methyl groups and the free acid groups

D-galacturonic acid
may be partly or fully neutralized with sodium, potassium or ammonium ions. The ratio of
esterified galacturonic acid groups to total galacturonic acid groups - termed the degree of
esterification (DE) - has vital influence on the properties of pectin, especially the solubility
and the gel forming characteristics. The highest DE that can be achieved by extraction of
natural raw material is approx. 75%. Pectins with DE from 20-70% are produced by control-
led de-esterification in the manufacturing process.

High ester pectin degree of esterification (DE) = 60 %

The DE of 50% divides commercial pectins into high ester (HM) and low ester (LM) pectin.
These two groups of pectin gel by different mechanisms.

HM-pectin require a minimum amount of soluble solids and a pH within a pretty narrow
range, around 3.0, in order to form gels. LM-pectins require the presence of a controlled
amount of calcium or other divalent cations for gelation and do not require sugar and/or
acid.
Degree of esterification of HM-pectins controls their relative speed of gelation as reflected

High ester pectins

Degree of esterification

Pectinic acids

Low esters pectins

Pectic acids

Increasing degree of polymerisation

Nomenclature of pectin substances

by the designations ‘slow set’ and ‘rapid set’ high ester pectin. Degree of esterification of
LM-pectins controls their calcium reactivity. Some types of LM-pectins also contain amide
groups, which strongly affects the calcium reactivity.

Acid demethylated

Amidated low ester pectin

General Properties of Pectin

SOLUBILITY
Pectin must be completely dissolved to ensure full utilization and to avoid heterogeneous
gel formation. Complete dissolution presumes dispersion without lumping; if pectin lumps
are allowed to form they are extremely difficult to dissolve. Pectin, like any other gelling
agent, will not dissolve in media where gelling conditions exist. HM-pectin thus becomes
increasingly difficult to dissolve as the soluble solids in the medium increases. It is
recommended that HM-pectin is dissolved at solids below 20% and preferably in water.

Dissolution with high-speed mixer

The simplest way of dissolving powdered pectin is by means of a high-speed mixer with
superior shearing action. In this way 4-8% solutions of pectins are easily made. With the
best mixers and using hot (min. 800C) water it is possible to make 10% solutions of most
pectins.

Preblending with sugar

When dry blended with 5 parts of sugar or more, pectin may easily be dispersed into water.
Fine mesh pectin may even at low concentrations dissolve readily into cold water by this
method. Using regular mesh pectin and conventional stirrers it is possible to make up to
approx. 4% pectin dispersions. At higher concentrations the viscosity of the batch becomes
a limiting factor for homogeneous dispersion.

To ensure complete dissolution of the pectin, it is recommended that the dispersion is

boiled for 1 minute. As dissolution of pectin becomes increasingly difficult at higher soluble
solids, the bulk of the sugar in the recipe should not be added until the pectin is dissolved.
Dispersing in concentrated sugar solution
As pectin does not dissolve at high sugar concentrations, it is possible to make a disper-
sion of pectin in a concentrated sugar solution without tendency to lump formation.
Depending on stirrer efficiency and process, 2 -12% pectin dispersions may be obtained
by this procedure.
Complete dissolution of the pectin requires dilution with water, optimally down to 20%
solids or below, followed by boiling for 1 mintue.

Viscosity
Pectin solutions usually show relatively low viscosities compared to other plant gums and
thickeners. Calcium or other polyvalent ions increase the viscosity of pectin solutions and
low ester pectin solutions may even gel if the calcium content exceeds a certain limit. The
viscosity of pectin solutions is also influenced by pH. In a calcium-free solution, the viscosity
drops when pH is increased from below the pK-value to above this value. Viscosity of a
pectin solution may be determined for the purpose of obtaining a measure of the molecular
weight of the pectin or for evaluating the thickening effect of the pectin. In the former case,
the viscosity must be determined in a calcium-free solution at a fixed pH, e.g. 4.0.

REACTIONS
Stability in solution
Most reactions which pectin undergoes in use tend to degrade the pectin. As a rule,
maximum stability is found at pH 4. The presence of sugar in the solution has a certain
protective effect while elevated temperatures increase the rate of degradation.

Per cent of max.

breaking strength

HM-pectin LM-pectin

Breaking strenth of pectin gels as a function of previous heat

treatment of the pectin (900C, 15 minutes) at various pH-values.

At low pH-values and elevated temperatures degradation due to hydrolysis of glycosidic

links is observed. De-esterification is also favoured by low pH. By de-esterification, a high
ester pectin becomes slower setting or gradually adapts low ester pectin characteristics.
At near-to-neutral pH (5-6), HM-pectin is stable at room temperature only. As the tempera-
ture (or pH) increases, a so-called ß-elimination starts. The ß-elimination results in chain
cleavage and very rapid loss of viscosity and gelling properties.

ß-elimination

LM-pectin shows a somewhat better stability at these conditions as illustrated in the graph
on page 12. At alkaline pH-values pectin is rapidly de-esterified and degraded even at
room temperature.

Reactions with other electrically charged hydrocolloids

Pectin is a polygalacturonic acid and the chain molecule is negatively charged at neutral
pH. The pK-value of pectin is approx. 3.5. Pectin reacts with positively charged macro-
molecules, e.g. proteins at pH-values below their isoelectric pH. Pectin precipitates gela-
tine at low pH-values, but this reaction can be prevented by addition of salt. When pectin is
added to milk at the pH of milk (6.6) a two-phase system is formed. At lower pH, pectin may
combine with casein particles present to produce a stable acidified milk, which may even
be heat treated to extend the shelf life of the product. Without pectin the milk protein would
agglomerate to cause „sandy“ mouthfeel and separation.

GELLING MECHANISM
A pectin gel may be regarded as a system in which the polymer is in a state between fully
dissolved and precipitated. It is theorized that segments of the molecule chains are joined
together by limited crystallization to form a three-dimensional network in which water, sugar
and other solutes are held.
Formation of a gel, from a state where the polymer is fully dissolved, is caused by physical
or chemical changes that tend to decrease the solubility of the pectin and this favours the
formation of local crystallization. The most important factors which influence the solubility
of pectin (tendency to gel) are:

1. Temperature
2. Molecular composition of the pectin (pectin type)
3. pH
4. Sugar and other solutes
5. Calcium ions
 Simplified model of the molecular network of a pectin gel.
Shaded areas represent local crystallization

Temperature
When cooling a hot solution containing pectin, the thermal motions of the molecules are
decreased and their tendency to combine into a gel network is increased. Any system
containing pectin at potential gelling conditions has an upper temperature limit above
which gelation will never occur. Below this critical temperature low ester pectins gel almost
instantly while the gelation of high ester pectins is time dependent, the time taken being
related to the temperature at which gelation occurs. In contrast to low ester pectin, high
ester pectin gels are not temperature reversible.

Gelling time, when cooled to and

HM-pectin Degree of subsequently held at
type esterification
950C 850C 750C 650C

Rapid set 73.5 60 min. 10 min. Pre-gel Pre-gel

Medium set 69.5 No gel 40 min. 5 min. Pre-gel

Slow set 64.5 No gel No gel No gel 30 min.

Gelation of HM-pectins with various DE (pH = 3.0, SS = 65%, pectin concentration = 0.43%)
Types of pectin
The overall distribution of hydrophilic and hydrophobic groups on the pectin molecule
determines the solubility (tendency to gel) of a particular pectin.

The degree of esterification of a high ester pectin influences the gelling properties. The
ester group is less hydrophilic than the acid group and consequently a high ester pectin
with a high degree of esterification gels at higher temperatures than a high ester pectin
with a lower degree of esterification. This difference is reflected in the terms rapid set,
medium set and slow set, which is illustrated in the above table.

The solubility of the calcium salt of completely de-esterified pectin (polygalacturonic acid)
is extremely low and a similar tendency to precipitate (form gels) in the presence of cal-
cium ions is found with low ester pectin. The lower the degree of esterification - the more
pronounced the similarity to polygalacturonic acid - and the greater the reactivity with
calcium as reflected in the higher gelling temperatures observed.

Introduction of amide groups into the LM-pectin molecule tends to make the pectin less
hydrophilic - increasing the tendency to form gels. In practice, amidated LM-pectins show
a wider „working range“ with regard to calcium content of the system and yield increasing
gelling temperatures with increasing degree of amidation.
Gelling temperature 0C

Degree of esterification

pH = 3.3 - SS = 45 %
Calcium: 15 mg/g pectin, pectin: 1%
pH
Pectin is an acid with a pK-value of approx. 3.5.

Dissociation (- charge density) of pectin at varying pH.

Increasing ratio of dissociated acid groups to non-dissociated acid groups generally makes
the pectin molecule more hydrophilic. The tendency to form gels is therefore strongly
increased by decreasing pH of the system. This is especially evident for high ester pectins
which normally require a pH below 3.5 in order to gel.

Sugar and other solutes

Sugar and similar solutes generally tend to dehydrate the pectin molecules in solution. At
higher solids there is less water available to act as a solvent for the pectin and the tendency
to crystallize or gel is consequently favoured.

Above 85% soluble solids, the dehydration effect is so strong that, in practice, gelation of
any commercial pectin can hardly be controlled. High ester pectins form gels at soluble
solids down to approx. 55%. For each soluble solids value above 55% there is a pH-value
at which gelation is optimum for a particular high ester pectin, and a pH-range within which
gelation can be obtained in practice.

Low ester pectins may gel at any soluble solids. For a particular pectin, the gelling tempera-
ture decreases with decreasing soluble solids.

Calcium ions
In contract to high ester pectin, low ester pectin forms gels in the presence of divalent
cations such as calcium. As illustrated below, acid-demethylated low ester pectins require
a fairly high amount of calcium within quite narrow limits to give optimum gel strength.
Amidated low ester pectins show greater flexibility in this respect. For both pectin types
increasing calcium concentration results in increasing gel strength - and increasing gelling
temperature - to a point where pregelation occurs. I.e. the gelling temperature close to the
boiling point.% of maximum gel strength

MG calcium per g-pectin

Amidated LM-pectin (standardized)

Acid demethylated LM-pectin (standardized)

Commercial Pectins
POWDER CHARACTERISTICS AND STORAGE STABILITY
The powder density of a typical standardized HM-pectin produced by alcohol precipitation
is 0.70.

A typical mesh specification says: 90% through a 60 mesh (0.25 mm) sieve. The colour of
a commercial pectin may vary from light cream to light tan for an alcohol precipitated pectin
or sometimes greenish yellow for an A1-precipitated pectin. Apple pectins are generally
darker than citrus pectins.

Commercial pectins will absorb water under most climatic conditions. Their equilibrium
water content are:

9% in an atmosphere of 50% relative humidity.

12% in an atmosphere of 70% relative humidity (valid for a 150 grade HM-pectin blended
from 70% pectin and 30% sucrose).

Pectins standardized with dextrose (9% water) have a higher moisture content than those
standardized with sucrose (0% water) and have correspondingly higher equilibrium water
contents in any atmosphere. Pectins are normally packed in vapour tight packaging label-
led

STORE COOL AND DRY.

Stability
Powdered HM-pectins lose about 5% in jelly grade per year when stored at room tempera-
ture. Furthermore, HM-pectin is slowly de-esterified during storage, whereby e.g. rapid set
pectin over a period of a year become a medium rapid set pectin. Degradation and de-
esterification rates are more than doubles when the storage temperature is increased from
200C to 300C. LM-pectins are more stable at storage than HM-pectins and degradation is
normally not detectable over a period of a year at room temperature.

STANDARDIZATION
Pectins are standardized by the manufacturers to ensure that the users always get the
same gel strength in their product and at the same point in the production process, provided
the pectin is used under the same constant conditions.

High ester pectin

Commercial HM-pectins are characterized by, and standardized to, uniform „jelly grade“
and gelling velocity. „Jelly grade“ expresses the amount of sugar than can be gelled in a
standard gel (standard composition and standard gel strength).

Various methods are used in measuring gel strength, the most common method being the
SAG-method, where deformation by gravity of the demoulded gel is measured. In other
methods, breaking strength of the gel is determined. For specific applications the ratio
between strength based on SAG-grade and strength based on breaking strength grade is
of importance. In jellies, specifically confectionery jellies, a high breaking strength is required,
whereas in jams the need for spreadability favours a pectin with a low breaking strength.
International trade gives preference to the SAG-method developed by the US IFT in 1959
and published in Food Technology 13, 496 (1959).

The majority of HM-pectins are standardized to 150 grade USA-SAG, which means that 1
kg of standardized pecitn will turn 150 kg of sugar into a standard gel (SS = 65.0%, pH =
2.2-2.4, gel strength = 23.5% SAG).

In other words:
1 kg 150 „jelly grade“ pectin can set 230 kg standard jelly.

Gelling velocity of an HM-pectin jelly may be expressed as setting time or as setting tempera-
ture. None of these two characteristics are physical constants as they vary with

a) the composition of the jelly, i.e. pH, SS, pectin concentration, etc.

b) the cooling rate of the jelly.

The setting temperature of and HM-pectin jelly is defined as the temperature at which the
first sign of jellification is observed. The setting time is defined as the time from the end
point of the jelly preparation to the first sign of jellification.

The most commonly used method for determination of gelling velocity is the Joseph Baier
method that enables gelling time and specifies the important variables as follows:

SS = 65%
pH = 2.2-2.4

Gel strength of test jelly = 23.5% SAG

Cooling rate = As obtained in a standard USA-SAG jelly glass

in a 300C water bath.

The test jelly is in fact exactly the same as the one used for the USA-SAG grade determi-
nation.

Low ester pectin

LM-pectin may be graded by a method with some similarities to the USA-SAG method
used for HM-pectin. The composition of the test jelly may for example be:

SS = 31.0%
pH = 3.0

Calcium concentration = 250 mg Ca/kg test jelly

or

25 mg Ca/g standardized 100 grade LM-pectin.

Jelly grade expresses the number of kg jelly of standard firmness (20.5% SAG) which can
be produced from 1 kg LM-pectin. As application conditions for LM-pectin show rather
wide variations, jelly grade methods are not always sufficiently relevant for the use of LM-
pectin. Performance tests may be used as sole or additional test procedure.

QUALITY CONTROL
Purity determination
The „pure pectin“ content is determined as percent anhydro-galacturonic acid by official
method of Food Chemicals Codex (FCC), Third Edition, Washington, D.C., 1981 (incl.
supplements), or as galacturonic acid by official method of FAO Food and Nutrition Paper
(FNP), 52, 1992. The method involves washing of powdered pectin in a mixture of
hydrochloric acid and 60% alcohol, which removes sugars and salts and converts the
pectin to its acid form. If the galacturonic acid content as calculated on the acid/alcohol
purified sample is low, it indicates the presence of non-uronic acid polysaccharide material
in the pectin, or a pectin of low purity and often of low gelling power. Citrus pectins of high
purity have a galacturonic acid content above 74%, which is the lower limit in USP XXII
specifications for pectin.
Content of heavy metals in pectin is determined by official methods as published in FCC,
FAO, FNP, EU Directive of 25th July, 1978 and USP XXII. A summary of various official
purity specifications is shown in the table down below. Microbiological quality is determined
by official methods.

Calcium reactivity
LM-pectins require a minimum calcium concentration in order to yield gels with desirable
properties. At too high calcium levels, pregelation and tendency to syneresis occur. The
„calcium working range“ - or calcium reactivity - of a specific LM-pectin depends primarily
on degree of esterification and degree of amidation, but is also influenced by degree of
uniformity within and among molecules of the pectin lot.

Thus, calcium reactivity is not only controlled by proper processing ocnditions, but also
through careful selection of suitable raw material. Calcium reactivity is evaluated in test
jellies with different concentrations of calcium. The test jellies may be similar to those used
for grade determination, except for calcium concentration.

OFFICIAL PURITY SPECIFICATIONS FOR COMMERCIAL PECTINS

Reference FAO FCC EU

Drying loss (volatile matter) max. 12% max. 12% max. 12%

Acid-insoluble ash max. 1% max. 1% max. 1%

Sulphur dioxide max. 50 mg/kg max. 50 mg/kg max. 50 mg/kg

Sodium methyl sulphate - max. 0.1% -

Methanol, ethanol and isopropanol max. 1% max. 1% max. 1%

Nitrogen content, amidated pectin - - max. 2.5%

Nitrogen content, pectins max. 2.5% - max. 0.5%

Galacturonic acid min. 65% - min. 65%

Total anhydrogalacturonides in
pectin component - min. 65% -

Degree of amidation max. 25% max. 25% max. 25%

Arsenic, ppm max. 3 max. 3 max. 3

Lead, ppm max. 10 max. 5 max. 10

Copper, ppm max. 50 - -

Zinc, ppm max. 25 - max. 25

Copper and zinc, ppm - - max. 50

Heavy metals (as Pb), ppm - max. 20 -

FAO FOOD AND NUTRITION PAPER, 52, 1992
JECFA specifications for identity and purity of food additives, 1994; (anti-caking agents,
buffering agents, salts, emulsifiers, enzymes, extraction solvents, flavouring agents and
miscellaneous food additives).

FOOD CHEMICALS CODEX, Third Edition, Washington, D.C., 1981, (incl. Supplements).

EU Council Directive of July 25, 1978, laying down specific criteria of purity for emulsifiers,
stabilizers, thickeners and gelling agents for use in foodstuffs (78/663/EEC) (plus updates).

Applications
FOOD APPLICATIONS
Pectin is first and foremost a gelling agent used to impart a gelled texture to foods, mainly
fruit based foods. the gelling ability is further utilized where stabilization of multiphase
foods is required, either in the final product or at an intermediate stage in the process.

The thickening effect of pectin is utilized mainly where food regulations prevent the use of
cheaper gums or where the „all natural“ image of a product is essential.

Jams and jellies

HM-pectin requires 55-85% sugar and pH 2.5-3.8 in order to gel. These requirements limit
the possible uses of HM-pectin as a gelling agent to sweetened fruit products and about
80% of the world production of HM-pectin is used in the manufacture of jams and jellies,
the pectin being added to make up for „deficiency of natural pectins.“

The role of pectin is to impart a texture to the jam or jelly that allows transportation without
changes, that gives a good flavour release and that minimizes syneresis. During manufacture
of a jam the pectin must ensure a uniform distribution of fruit particles in the continuous
jelly phase from the moment the mechanical stirring ceases, i.e. the pectin must set quickly
after the filling operation. The use concentrations for pectin vary from 0.1-0.4% in jams and
jellies.

Pectin gelation can be obtained in a cold process by mixing a pectin-sugar-syrup with

soluble solids 60-65% and pH 3.8-4.2 with fruit acid solution to achieve pH 3.0. This process
is used in Scandinavia by the bakers to make jelly-covered fruit tarts. A variation of the
technique is mixing a pectin solution with pH 2.9 and soluble solids 25% with a liquid sugar
to obtain soluble solids 53%.

These two processes can be used as a result of gelation of HM-pectin being time, as well
as temperature. dependent.

The traditional application of LM-pectin is in jams with soluble solids below 55%, which is
the limit for the use of HM-pectin. The calcium content of the fruit is normally sufficient to
set an amidated LM-pectin, whereas acid demethylated LM-pectin requires addition of a
calcium salt. The type of LM-pectin must be carefully selected according to the soluble
solids/pH conditions in the application medium. In products with very low solids, as for
instance sugar-free jams for diabetics, LM-pectin hardly has sufficient water binding and a
carrageenan is better suited. In some instances combinations of LM-pectin and carrageenan
offer advantages.

The heat reversibility of LM-pectin gels may be utilized in bakery jams and jellies for glazing
purposes. A jam or jelly base with soluble solids of approx. 65% has a relatively good
microbiological stability, but the LM-pectin only imparts a paste-like texture to the product,
due to pregelation. Prior to application, the base is diluted with water to approx. 40% solids
and heated to remelt the LM-pectin gel. When poured on top of cakes and tarts, the LM-
pectin gels optimally at the reduced solids to form a coherent and glossy glazing.

Fruit preparations for yoghurt

Low ester pectins are often used in fruit preparations for yoghurt to create a soft, partly
thixotropic gel texture, sufficiently firm to ensure uniform fruit distribution but still allowing
the fruit preparation to be easily stirred into the yoghurt. The pectin may further - especially
when combined with other plant gums - reduce colour migration into the yoghurt phase of
the final product.

Fruit drink concentrates

Gelation of pectin may be used as a means of stabilizing a multiphase system if gelling
conditions can be achieved at some stage in the process. Gelation provides the yield value
which is required to obtain permanent stbilization of emulsions, suspensions and foams.
HM-pectin is used in fruit drink concentrates, stabilizing any oil emulsions and fruit particle
suspensions. In this application the gelation is apparent in the end product only as a
thickening effect, as the coherent gel texture has been broken mechanically to obtain a
smooth flow. Extensive homogenization must not be used, as sufficient yield value must
still be present to ensure stabilization.

Fruit juice
The viscosity or mouthfeel creating properties of HM-pectin find use in recombined juice
products to restore the mouthfeel of the juice to that of the fresh juice. Pectin is further used
to provide a natural mouthfeel in instant fruit drink powders.

Fruit/milk desserts
The calcium response of LM-pectin may be utilized to obtain an instant gelation when
adding calcium ions (milk) to a syrup containing LM-pectin. A canned fruit preparation
containing 2% LM-pectin in a fruit syrup with 25-30% soluble solids and pH 4.0 is mixed
with an equal amount of cold milk to quickly make a fruit flavoured semi-gelled milk des-
sert.

LM-pecitn has excellent stability at the conditions of fruit preparation manufacture, i.e. pH
4.0 and suitable pasteurization conditions. The LM-pectin solution remains fluid at room
temperature as calcium content is insufficient to cause gelation. When the fruit preparation
is mixed with milk, sufficient calcium is available to gel the LM-pectin.

Another version of this basic idea is a concentrated, sweetened and flavoured LM-pectin
solution, a paste to be mixed into three parts of cold milk. The ‘intermediate moisture food’
properties of this concept imply a wider pH-range allowing vanilla or chocolate flavouring
to be used.

A third version is a powder to be dissolved in cold water prior to addition of milk.

Fermented and directly acidified dairy products
The ‘protective colloid’ effect of HM-pectin is utilized to stabilize sour milk products either
cultured or produced by direct acidification (fruit juice-milk combinations).

The pectin reacts with the casein, prevents the aggregation of casein particles at pH below
the isoelectric pH (4.6) and allows pasteurization of the sour milk products to extend their
shelf life.

The texture of yoghurt may be improved by small amounts of LM-pectin which is added
before the yoghurt milk is heated. The LM-pectin does not prevent syneresis.

Gelled milk products

LM-pectin is suited as a gelling agent in milk desserts, but less economical in use than
carrageenan, whicih gels milk a much lower use concentrations.

LM-pectin may, however, be preferred as gelling agent for sour milk puddings or milk des-
serts combined with fruit. Unlike carrageenan, LM-pectin does not co-precipitate with casein
at reduced pH-values and thus ensures a reasonable shelf life of the product.

Confectionery products
High ester pectin is mainly used within the confectionery industry for making fruit jellies
and jelly centres, flavoured with natural fruit constituents and/or synthetic flavours. In
combination with whipping agents it is further used as a texturizer for aerated fruit flavoured
products.

Low ester pecitn not requiring addition of acid for gel formation is used for jellies and
centres in which the low pH-range necessary for HM-pecitn gelation is not acceptable for
flavour reasons (e.g. peppermint or cinnamon flavoured jellies).

At low concentrations, LM-pectin may further impart a thixotropic texture to confectionery

fillings. At higher concentrations a cold gelation can be obtained if calcium ions are allowed
to diffuse into the filling.

Compared to other gelling agents commonly used for confectionery products, pectin requires
strict observance of the recipe and production parameters, but offers the advantage of a
very fine texture and mouthfeel, excellent flavour release and compatibility with modern
continuous processing due to a fast and controllable gelation.

PHARMACEUTICAL APPLICATIONS
The ability of pectin to add viscosity and stabilize emulsions and suspensions is utilized in
a number of liquid pharmaceutical preparations.

Pectin is further reported to possess a number of valuable biological effects - the most
well-known being an anti-diarrhoea effect. Anti-diarrhoea suspensions, powders or tablets
often contain a mixture of koalin, pecitn and a antibiotic.

Pectin is extensively used as a component in the adhesive part of ostomy rings. In this
application the water binding effect and the ability to adhere to moist surfaces are utilized.
Pectin is further non-irritating in contact with the skin, and certain bactericidal and wound
healing effects have even been reported.
GENU Pectins
GENU is the trademark for pectins marketed by CP Kelco ApS, founded in 1934. CP Kelco
ApS is the largest, most modern and automated pectin manufacturing plant in the world
today. GENU pectins are marketed in more than sixty countries.

GENU pectins have established their position as uniform gelling agents of high quality for
jams, jellies and marmalades. GENU pectins are finding increasing use in particular as
gelling agents, but also as viscosity builders, protextive colloids and stabilizers in a number
of other foods, in beverages and in pharmaceutical and cosmetic products. In the research
and application laboratories of CP Kelco ApS formulations and processing methods for
new and traditional food products are continuously developed and perfected.

In close contact with the industry new pectin types and production processes are further
developed to meet specific demands and new technology within the market.

Customer service is considered a very important part of the activities of CP Kelco ApS.
Individual technical advice is available free of charge throughout the world either by contact
to our local sales representatives or directly from

CP Kelco ApS
DK-4623 Lille Skensved
Denmark

Telephone: +45 56 16 56 16
Telefax: +45 56 16 94 16

www.cpkelco.com
email: solutions@cpkelco.com

ADDITIONAL TECHNICAL LITERATURE is available, such as:

Application Guides, Confectionery, Fruit Products, Dairy Products,

Bakery Products, Meat Products
Handbook for the Fruit Processing Industry
Product Information sheets
Control Methods
Purity Specifications
Safety Data Sheets
Nutritional Information
Application Notes with individual recipes suggestions