CONTENTS 



CHAPTER I 



MILK SECRETION 1-14 



The purpose of milk secretion 1 



Physiology of the mammary gland .... 2 



The elaboration of milk in the animal organism . . 4 



Early theories 4 



Present theories ....... 7 



Rate of activity in mammary gland .... 9 



Factors which affect milk secretion . 10 



CHAPTER II 



THE CHEMICAL COMPOSITION OF MILK . . . . 15-39 



Variation in normal cow's milk 19 



The fats of milk 20 



The composition of milk-fat 20 



The non-volatile fats 22 



The volatile fats 22 



The serum of milk 23 



The proteids or albuminoids .... 23 



Casein 24 



Albumin or lact-albumin .... 24 



Lactoglobulin 24 



Galactin 24 



Fibrin 25 



Milk-sugar 27 



Citric acid 28 



The mineral constituents or ash 28 



Other constituents of milk 29 



Condition of casein and salts in milk ... 29 



Properties and composition of milk-serum . 31 

 Properties and composition of that part of milk in 



suspension or colloidal solution . . 34 

 vii 



