Ifo. 6. 



DEPARTMENT OF AGRICULTURE. 



•31 



(1.) Proportion of Milk-Fat Lost m Cheese-Making in Different 

 Milks. — Careful and extensive investigations have shown clearly that 

 (he amount of fat lost in the process of cheese-making varies com- 

 paratively little whether the milk contains more or less fat. The 

 followiiig tabulated summary represents averages obtained with 

 a very large number of experiments carried on by the writer with 

 normal milk varying in fat content fiom 3 to over 5 per cent.: 



An examination of the figures in the third column, shows that 

 about the same amount of fat is lost in the whey for one hundred 

 pounds of milk, whether the milk contains 3 per cent, or more of fat. 

 Looking at the figures in the last column, we see what proportion 

 of the fat in milk is lost in the whey. Thus, when the milk contains 

 3 to 3.5 per cent, of fat, 0.32 pound of this fat is lost for 100 pounds 

 of milk, which is 9.55 per cent, of the amount of fat in the milk. The 

 proportion of fat grows actually less as the milk, becomes richer in 

 fat. As a rule, the loss of fat in cheese-making is quite independent 

 of the amount of fat in milk. 



(2.) Amount of Casein in Different Milks. — In regard to the second 

 assumption made above, that the amount of casein is practically 

 constant in all kinds of milk, we can say that our work and the 

 work of others does not justify the statement. As a rule, when fat 

 in milk increases, the casein also increases, though not in quite the 

 same proportion. Above 4.5 per cent, of fat, the casein appears to 

 increase less rapidly than in milks containing less than 4.5 per cent, 

 of fat. In the tabulated data given below, one can see about how 

 fat and casein are related to each other in milk containing different 

 amounts of fat: 



