CHAPTER XXIV 



MILK AND MILK PRODUCTS; DAIRY FARMS 



DAIRYING comprises two occupations, dairy husbandry, or 

 the producing of milk ; and dairy industry, or the marketing and 

 manufacturing of milk and milk products. This chapter is designed 

 to compass chiefly some phases of the latter subject. 



Composition of Milk 



Composition of cow's milk 



Fat in milk is in the form of minute globules having a diameter of 

 i-sinsv to ssW of an inch. These float in the milk, forming an emulsion. 

 When highly magnified, these fat globules may be easily seen. In any 

 milk, many different sizes of globules are found, but the average size of 

 globules in Jersey and Guernsey milk is much larger than the average 

 size of globules in the milk given by other breeds. As the specific 

 gravity of the fat is .93 and the specific gravity of the remainder of the 

 milk is about 1.04, the fat globules always tend to rise. They are more 

 or less entangled by other constituents of the milk, and great numbers 

 of the smallest sized globules fail to reach the top, or the cream layer 

 (Pearson). 



Milk-fat is a mixture of several different fats which are combinations 



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