90 Rrt'out of tiir Chemist of tiir 



2. DiPPEUENCB IN Chebsk-Prodtjcing Power of Milk-Fat in 



DlFFERENT MiLKS. 



From 100 pounds of milk containing 3 i)er cent of fat, we have 

 a yield of 8.55 pounds of cheese; from 100 pounds of milk con- 

 taining 4 per cent of fat, we have a yield of 10.4 pounds of 

 cheese. The increased yield of cheese from 100 pounds of milk is 

 due to the added amount of fat and casein contained in the richer 

 milk. In the milk containing 3 per cent of fat, there are made 

 2.85 pounds of cheese for each pound of milk-fat; in the milk 

 containing 4 per cent of fat, there are made 2.60 pounds of 

 cheese for each pound of milk fat. The difference between 2.85 

 and 2.60 equals 0.25 pounds. Now, what makes this extra yield 

 of 0.25 pounds of cheese for each pound of fat in the case of the 

 milk containing 3 per cent of fat? Is it due to fat? It cannot 

 be, as the figures are based on one pound of fat iu both cases. 

 It must then be due to the fact that the milk poorer in fat con- 

 tains more casein for a pound of fat than does the milk richer in 

 fat. This increased yield of 0.25 pounds of cheese for a pound of 

 milk-fat comes from casein and the ivater lohich it absorbs. Take 

 out this casein and water and the yield for a pound of fat would 

 be the same in rich and poor milk. 



3. Market Value of Casein and Water in Cheese. 



In the table below we have indicated the amount of fat, casein 

 and cheese obtained from 100 pounds of milk ranging from 3 to 

 4 per cent of fat and varying by one-tenth of one per cent of fat. 

 In column 4 is given the amount of cheese made for each pound 

 of fat in milk. 



In column 5 we give the amount of cheese which would be 

 made from 100 pounds of milk, if each milk contained for (^ach 

 pound of milk-fat the same amount of casein as is contained in 

 the milk containing 4 per cent of milk-fat. In other words, these 

 figures represent cheese having the same identi<^al composition 

 as cheese made from the milk containing 4 per cent of fat. We 

 have simply removed the excess of casein in the poorer milks. 



In column 6 is given the amount of casein removed from each 

 milk in oi'der to make llic relation of fal and casein uniform with 



