Food Biochemistry and Food Processing (2 edition)

BLBS102-c24 BLBS102-Simpson March 21, 2012 13:47 Trim: 276mm X 219mm Printer Name: Yet to Come

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Chemistry and Biochemistry

of Milk Constituents

P.F. Fox and A.L. Kelly

Introduction

Saccharides

Lactose

Introduction

Chemical and Physico-Chemical Properties of Lactose

Food Applications of Lactose

Lactose Derivatives

Nutritional Aspects of Lactose

Lactose in Fermented Dairy Products

Oligosaccharides

Milk Lipids

Definition and Variability

Fatty Acid Profile

Conjugated Linoleic Acid

Structure of Milk Triglycerides

Rheological Properties of Milk Fat

Milk Fat as an Emulsion

Stability of Milk Fat Globules

Creaming

Homogenisation of Milk

Lipid Oxidation

Fat-Soluble Vitamins

Milk Proteins

Introduction

Heterogeneity of Milk Proteins

Molecular Properties of Milk Proteins

Interspecies Comparison of Milk Proteins

Casein Micelles

Minor Proteins

Immunoglobulins

Blood Serum Albumin

Metal-Binding Proteins

β 2 -Microglobulin

Osteopontin

Proteose Peptone 3

Vitamin-Binding Proteins

Angiogenins

Kininogen

Glycoproteins

Proteins in the Milk Fat Globule Membrane

Growth Factors

Milk Protein-Derived Bioactive Peptides

Indigenous Milk Enzymes

Nutritional and Protective

Technological

Indices of Milk Quality and History

Antibacterial

Milk Salts

Vitamins

Summary

References

Abstract:Mammalian milk is a highly complex physicochemical

system, containing colloidal proteins (the casein micelle) and emul-

sified lipids, as well as dissolved lactose, minerals, vitamins and

minerals. The properties of milk, and the products made or isolated

from milk, are very much determined by the properties of its con-

stituents. These properties are particularly relevant when milk is

processed, for example through denaturation of proteins, oxidation,

hydrolysis of proteins and lipids, or Maillard reactions involving

lactose. In this chapter, the principal families of milk constituents,

and their most significant characteristics, are described.

INTRODUCTION

Milk is a fluid secreted by female mammals, of which there are

approximately 4500 species, to meet the complete nutritional,

and some of the physiological, requirements of the neonate of the

species. Because nutritional requirements are species-specific

and change as the neonate matures, it is not surprising that

the composition of milk shows very large interspecies differ-

ences, for example the concentrations of fat, protein and lactose

range from 1% to 50%, 1% to 20% and 0% to 10%, respec-

tively. Interspecies differences in the concentrations of many of

Food Biochemistry and Food Processing, Second Edition. Edited by Benjamin K. Simpson, Leo M.L. Nollet, Fidel Toldr ́a, Soottawat Benjakul, Gopinadhan Paliyath and Y.H. Hui.

©C2012 John Wiley & Sons, Inc. Published 2012 by John Wiley & Sons, Inc.

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