Food Biochemistry and Food Processing

26

Dairy Products

T. D. Boylston

595

Introduction
Biochemistry of Cultured Dairy Products
Composition of Milk
Lactic Acid Bacteria
Key Processing Steps in Cultured Dairy Products
Lactose Fermentation
Coagulation of Milk Proteins
Homogenization
Pasteurization
Cooling
Processing of Cultured Dairy Products
Cheese
Natural Cheeses
Standardization of the Milk
Coagulation of the Milk Proteins
Cutting the Coagulum
Shaping and Pressing
Salting
Ripening
Processed Cheese
Butter
Buttermilk
Sour Cream
Yogurt
Acidophilus Milk
The Future—Cultured Dairy Products with Therapeutic
Benefits
Acknowledgment
References
General References
Cited References

INTRODUCTION

Fermented dairy products were originally developed
as a means to preserve milk through the production

of lactic acid. However, these products are also rec-

ognized to have desirable sensory characteristics

and nutritional value. The term, cultured dairy prod-

ucts, is currently used to indicate that these products

are prepared using lactic acid bacteria (LAB) starter

cultures and controlled fermentation. LAB utilize

the nutrients in milk to support their growth. The

production of lactic acid reduces the pH of these

products to inhibit the growth of many pathogenic

and spoilage microorganisms. In addition, the fer-

mentation process develops a wide range of dairy

products with a diversity of flavor and textural at-

tributes, including cheese, yogurt, buttermilk, butter,

acidophilus milk, and sour cream.

Chapters 19 and 20 provided detailed information

on the biochemistry and processing of milk and milk

products. This chapter will focus on the biochem-

istry and processing involved in the formation of

cultured dairy products. This chapter will include a

general discussion of the biochemistry and process-

ing of cultured dairy products, followed by a discus-

sion of the processing of the individual dairy prod-

ucts.

BIOCHEMISTRY OF CULTURED

DAIRY PRODUCTS

COMPOSITION OFMILK

The quality of the cultured dairy products is influ-

enced by the composition and quality of the raw

milk. Species, breed, nutritional status, health, and

stage of lactation of the cow can have an impact on

Food Biochemistry and Food Processing

Edited by Y. H. Hui

Copyright © 2006 by Blackwell Publishing