Dairy Ingredients for Food Processing

Dairy Ingredients in Dairy Food Processing 447

Fruit Preparations for Flavoring

Yogurt. The fruit preparations for blending

in yogurt are specially designed to meet

the marketing requirements for different

types of yogurt. They are generally present

at levels of 8% to 15% in the fi nal prod-

uct. Special fruit bases are designed for use

in stirred yogurt. They generally contain

0.1% artifi cial fl avor or 1.25% natural fl avor,

0.1% potassium sorbate, and an appropriate

level of coloring. The pH is adjusted to

3.8 to 4.2, depending on the particular

fruit. Calcium chloride and certain food -

grade phosphates are also used in several

fruit preparations. The soluble solids range

from 60% to 65% and the viscosity is stan-

dardized. To avoid unnecessary contamina-

tion of yogurt, aseptically packaged sterilized

talline fructose may be used in conjunction
with aspartame and other high - intensity
sweeteners to round up and improve the
overall fl avor of light yogurt. Up to 8% corn
syrup solids are used in frozen yogurt.
Commercial yogurts contain an average of
4.06% lactose, 1.85% galactose, 0.05%
glucose, and pH of 4.40.
Stabilizers. Stabilizers (generally 0.5% to
0.7%) in yogurt produce smoothness in body
and texture. Commonly used stabilizers
include gelatin; starches; vegetable gums
such as carboxymethyl cellulose, locust bean,
and guar; seaweed gums such as alginates
and carrageenans; and pectin. Whey protein
concentrate is commonly used as a stabilizer,
exploiting the water - binding property of
denatured whey proteins.

Table 17.16. Required and optional composition of yogurt bacteria.

Required by FDA standard of identity for yogurt Optional additional culture used or suggested

Streptococcus thermophilus (ST) Lactobacillus acidophilus

Lactobacillus delbrueckii subsp. bulgaricus (LB) Lactobacillus casei

Lactobacillus casei subsp. rhamnosus

Lactobacillus reuteri

Lactobacillus helveticus

Lactobacillus gasseri ADH

Lactobacillus plantarum

Lactobacillus lactis

Lactobacillus johnsoni LA1

Lactobacillus fermentum

Lactobacillus brevis

Bifi dobacterium longum

Bifi dobacterium breve

Bifi dobacterium bifi dum

Bifi dobacterium adolescentis

Bifi dobacterium animalis

Bifi dobacterium infantis

Bifi dus ActiRegularis ™

Adapted from Chandan (1999, 2004)

Table 17.17. Growth temperature profi le of yogurt organisms.

Growth

Temperature

Streptococcus

thermophilus ° C

Lactobacillus delbrueckii

subsp. bulgaricus ° C

Maximum 50 50 – 52

Minimum 20 15

Optimum 39 – 46 40 – 47

Adapted from Chandan and Shahani (1993)