Texturising of Ferm Milk Products - Herbstreith & Fox · protein gel, is an integral part ......

Texturisingof Fermented Milk Products

FROM RESEARCH

& DEVELOPMENT

HERBSTREITH & FOX Corporate Group • Turnstraße 37 • 75305 Neuenbürg/Württ. • Germany

Phone: +49 7082 7913-0 • Fax: +49 7082 20281 • [email protected] • www.herbstreith-fox.de

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TEXTURISINGof Fermented Milk Products

Set yoghurts, stirred or layered fruit yoghurts,

curd cheese and buttermilk desserts with their

undisputedly fresh and healthy image have

always been very popular with the consumer.

Fermented milk, the so-called "white mass", a

protein gel, is an integral part of all of these

products.

In the past years, virtually boundless combina-

tion possibilities with fruit, pastry or also

functional components, in conjunction with

optimised manufacturing technologies have re-

sulted in innovative additions to product ranges

in this field, such as the introduction of seasonal

products or products aimed at specific target

groups.

This has strengthened and even expanded the

market position of these products.

The consumer has very high demands on fer-

mented milk products. A typical taste, an appea-

ling look as well as a very specific consistency

are expected.

Both the recipe and the manufacturing techno-

logy are extremely important for the quality of

yoghurt or curd cheese products.

During the fermentation of milk, the proteins

undergo structural changes. Casein micelles

agglomerate, forming a three-dimensional net-

work, the characteristic acid gel. Constitution

and stability of this gel structure greatly depend

on the raw material used, the processing of the

raw material, the fermentation and on the pro-

cess. Subjecting the raw material to heat treat-

ment or increasing the solids content of the milk

by adding, for example, skimmed milk powder

or whey proteins, has a positive effect on the

gel structure. In stirred products, the process

after fermentation has to ensure that a maxi-

mum of this structure is maintained in the form

of viscosity.

Pectin is a heteropolysaccaride with partly este-

rified polygalacturonic acid as its main compo-

nent and is mostly obtained from the raw mate-

rials apple pomace and citrus peel. One distin-

guishes between high methylester, low methyl-

ester and low methylester amidated pectins, all

of which differ in their stabilising, gelling and

thickening properties.

In the white mass application, pectin adds a

smooth texture as well as surface gloss to the

products and prevents or reduces serum sepa-

ration during storage and transport.

In this application, pectin is added as a stabili-

sing agent before fermentation. The stabilising

effect occurs as a result of a partial coating of

the protein surface by the pectin, which contri-

butes to the strengthening of the casein net-

work and thus the solidification of the acid gel.

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Acid gels are relatively weak gels and have

therefore a tendency to serum separation, the

so-called syneresis. This impairs the transporta-

bility of the products. Syneresis may also occur

during storage, especially at higher temperatu-

res, due to the contraction of the acid gel. This

increasingly occurs in low-fat and low-soluble-

solids products.

In order to prevent or reduce the tenden-

cy to syneresis, the solids content of the

milk can be increased. More interesting is

stabilisation using a hydrocolloid, as – be-

sides reducing the tendency to syneresis

– adding a hydrocolloid may also enhance

organoleptic properties, such as body,

mouthfeel, firmness, creaminess and sur-

face habit.

To prevent syneresis in and to add texture

to the white mass, starch, gelatine, agar-

agar and, ever increasingly, pectins are

used.

As a fruit component with a generally

positive image, pectin has long been used

as a stabilising agent in drinking yoghurt

products. Here pectin acts as a protective colloid

inhibiting protein agglomeration and protecting

the proteins towards dehydration and sedimen-

tation during thermisation.

Also by texturising of fermented milk products,

pectins have the benefit of being a natural and

thus consumer-friendly food additive that is

also of economic interest on account of its low

dosage.

Pectin Amid CM 025-A, a combination of speci-

fically selected pectins, is recommended for the

production of set yoghurts. Adding this pectin

type at an optimum dosage yields a smooth and

firm yoghurt gel. The tendency to syneresis,

which increasingly occurs in low-fat and low-

soluble-solids products is significantly reduced.

Pectin can completely or partially replace the

milk powder, which is added to increase the

solids content, and therefore contribute to cost

reduction. The improved storage and transport

stability of the products is a further benefit.

Stirred yoghurts should have a creamy texture

and should be able to be stirred easily and

smoothly even at high viscosity. Pectin Amid

CM 025, another specifically selected pectin, can

help fulfil these requirements. A smooth and

glossy surface, good structure and a low ten-

dency to syneresis bestow on products made

with this pectin an optimum appearance also

over longer storage periods and provide them

with stability during transport.

The benefits of Pectin Amid CM 025-A may

also be utilised for stirred yoghurts.

Depending on recipe, technology and required

effect in the final product the pectins are used

in a dosage range of 0.05 - 0.2%.

Mainly soy but also other vegetable proteins

more and more are used as raw material in

fermented products alternatively to milk pro-

teins. To gain required product properties like

firmness, viscosity etc. pectins there can be

used as well.

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As watersoluble hydrocolloids, pectins also form

strong hydrated zones resulting, on the one

hand, in a creamy mouthfeel and, on the other

hand, in a reduced tendency to syneresis.

As pectin is added before fermentation, an opti-

mum stabilisation dosage – as recommended –

is of utmost importance in order to prevent the

coagulation of the neutral milk (sweet coagula-

tion), which would result in a grainy, unstable

product.

To meet the various demands made on yoghurt

and curd cheese products Herbstreith & Fox has

a whole range of pectin types on offer. In this

application, low methylester and low methyl-

ester amidated pectins are used.

Pectin Amid CM 020 and Pectin Classic AM 901

have been used for years in the stabilisation of

the white mass:

• Pectin Amid CM 020 is an all-round pectin

that is used in both set and stirred yoghurts.

This pectin type reacts most flexibly and can

be used with any type of yoghurt process

control without a problem.

• The non-amidated Pectin Classic AM 901 is

the first choice in organic products, often in

combination with other hydrocolloids.

In addition to the above standard types, H&F

has developed two new pectins that are cus-

tom-tailored to the varying demands on set

and stirred yoghurts:

• Pectin Amid CM 025-A

• Pectin Amid CM 025

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Furthermore, by the use of a combination with

Herbacel AQ Plus Citrusfaser* a further increase

of the stability can be achieved. Additionally,

the white mass shows an extremely creamy

texture and a pleasant mouthfeeling at a very

PRODUCT OVERVIEW - H&F PECTINS

low tendency to syneresis. With the use of

Herbacel AQ Plus the product can additionally

be called “high-fibre” if the dosage of fibres

corresponds with the legal standards.

*Herbacel AQ Plus Citrus Fibre is a product of HerbafoodIngredients GmbH, www. herbafood.com

Pectin Amid CM 020 amidatedcitrus pectin

application in set and stirredfermented milk products

increase of firmness andreduction of syneresis

Pectin Amid CM 025 amidatedcitrus pectin

preferred in stirred fermentedmilk products

increase of viscosity and creaminess, smooth and glossy texture, reduction of syneresis

Pectin Amid CM 025-A amidatedcitrus pectin

preferred in set fermented milkproducts, but also benefits instirred fermented milk products

increase of firmness, smooth surface, smooth gel, reduction ofsyneresis

Pectin Classic AM 901 apple pectin application in set and stirredfermented milk products, espe-cially in organic products oftenin combination with otherhydrocolloids

increase of firmness, reduction of syneresis

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RESEARCH AND DEVELOPMENT

HERBSTREITH & FOX CORPORATE GROUP

24/01/2007

Set and Stirred Yoghurt

Product Pectin Amid CM 020

1.2g Pectin (= 0.12%)

30g skimmed milk powder

60g sucrose

909g whole milk

yoghurt culture

Input: approx. 1000g

pH-value: approx. 4.6

• Mix dry ingredients (pectin, skimmed milk powder and sugar)

• Stir mixture into cold milk (Ultra Turrax®)• Leave to swell for 1 hour• Heat solution to 85°C, 20 minutes• Homogenise at 100 bar• Leave to cool to 43 - 45°C• Add yoghurt culture, fill into containers• Allow to ferment to a pH-value of 4.5 - 4.6• Leave yoghurt to cool to 7°C

Herbstreith & Fox KG Recipe

In the manufacture of stirred yoghurt the yoghurt is being glazed after acidification and

cooled to 20°C. Then the fruit preparation (20%) is mixed in the yoghurt before bottling.

In set and stirred yoghurt pectins provide texture and prevent syneresis.

Herbstreith & Fox offers pectins to stabilise

fermented products like set or stirred yogurts,

curd cheese or buttermilk desserts as well as

soy yogurts and to give them their structure.

These pectins offer the opportunity to the user

to reach special product properties accordant

to his demands and possibilities.

Texturising of Ferm Milk Products - Herbstreith & Fox · protein gel, is an integral part ......

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Transcript of Texturising of Ferm Milk Products - Herbstreith & Fox · protein gel, is an integral part ......