DAIRY CATTLE AND THEIR PRODUCTS 167 



on the market, is not the most important food constituent of 

 milk. Butter fat is composed mainly of nine different fats. 

 On account of the importance of the fat, it is often made the 

 basis of payment for milk. By means of the Babcock tester 

 the amount of butter fat in milk can be accurately deter- 

 mined. This amount ranges from" 2 per cent to 6 per cent. 

 Cream contains most of the butter fat in milk, and it thus 

 becomes an important item to separate the cream from the 

 milk in order to get the greatest amount of butter fat. Experi- 

 ments have shown that from the three methods of cream 

 separation the following results were obtained : 



Butter Lost in Skim-Milk from 1 Cow in 1 Year 



Hand separator Loss of butter 2.6 Ibs. 



Shallow pan Loss of butter 60. Ibs. 



Water dilution Loss of butter 70. Ibs. 



It is easily seen that a good hand cream separator is a 

 profitable piece of apparatus to have on the farm keeping 

 three or more cows. 



Cheese. We learned that casein is one of the constituents 

 of milk. It contains protein, one of the most important food 

 elements of milk. This casein is separated as curd by the 

 souring of milk, but the separation may also be made by 

 adding cheese-making rennet. The curd formed by the ren- 

 net is then heated, the whey drained off, and later run 

 through a mill and cut into small pieces, salted, pressed 

 to form, and finally cured in a cool room before it is ready 

 for the market. 



Cheese is one of the most nutritious of foods and should be 

 more largely used in our diet. 



