46 Report op the Chemist of the 



average increase amounting to 0.22 pound of casein for 100 pounds 

 of milk. 



4. Variations in Relation op Casein to Fat in Milk. 



We have already seen in what manner fat and casein, the 

 cheese-producing constituents of milk, varied during the differ- 

 ent months of the season of 1895. It will be interesting to con- 

 sider these two compounds together. We will present the data 

 so as to show the number of pounds of casein for each pound of 

 fat contained in milk. It should be kept in mind that when the 

 proportion of casein to fat increases, the yield of cheese for each 

 pound of fat also increases. 



There is another point concerning the relation of fat and 

 casein in milk in respect to the bearing which this relation has 

 upon the methods of manufacture. In the months of July and 

 August, cheese-makers often complained of the behavior of the 

 cheese made at this time, without understanding the cause of 

 their diflSculty. The cheese leaked fat badly and did not stand 

 up well, although behaving properly when first made. This be- 

 havior is due to a decrease of casein and increase of fat, so that 

 the milk and cheese contained an excess of fat. Cheese-makers, 

 at such times, are really dealing with milk which is not normal 

 factory milk, but which is like normal factory milk to which 

 some cream has been added. 



