FARM ANIMALS 



34i 



It floats in the milk in globules, varying in size accord- 

 ing to the breed and the feed and the individual cow. 

 The fat rarely reaches 7 per cent of the bulk of the 

 milk, the highest grade dairy breeds, like the Jersey 

 and Guernsey, averaging about \\ per cent. 



Cream. When milk stands for a short time, the 

 fat rises to the top in the form of cream. Formerly 

 milk was placed in shallow vessels and the cream was 

 skimmed off and made into butter. By this method 

 one fourth of the butter fat is lost in the skimmed milk. 

 The deep-setting system is now more extensively prac- 

 ticed. Cans nearly two feet deep are used. They 

 are set from 12 to 24 hours in water 8 degrees to 10 

 degrees above freezing point. A conical dipper is used 

 for skimming, or a faucet in the bottom is opened and 

 the skim milk drawn off and then the cream. By this 

 method only one tenth to one fifth of the cream is lost 

 in the skimmed milk. 



The method most commonly used, however, and the 

 one that results in the least loss of butter fat is the 

 centrifugal separator, by means qf which the cream and 

 milk are separated. The fresh milk pours in a con- 

 tinuous stream into a revolving bowl. The milk, 

 being heavier than cream, is thrown to the outer part 

 of the bowl, where there is placed an opening to carry 

 it off. In the center is an opening through which the 

 cream passes. A good separator loses only about 

 .0003 of fat in skim milk or one fiftieth of the total 

 amount of butter fat. 



Casein. -This is the ingredient in milk that forms 

 the curd when milk sours. It is the foundation of 

 cheese, as butter fat is of butter, forming about one 

 third the bulk of the finished product. 



