MARKET DAIRYING. 
CHAPTER I. 
CHEMICAL AND PHYSICAL PROPERTIES OF MILK. 
Milk, in a broad sense, may be defined as the normal 
secretion of the mammary glands of animals that suckle 
their young. It is the only food found in Nature con- 
taining all the elements necessary to sustain life. More- 
over it contains these elements in the proper propor- 
tions and in easily digestible and assimilable form. 
Microscopic appearance of milk showing relative size of fat globules and 
bacteria.—Russell’s Dairy Bacteriology. 
Physical Properties. Milk is a whitish opaque fluid 
possessing a sweetish taste and a faint odor suggestive 
of cows’ breath. It has an amphioteric reaction, that is, 
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