296 MANUAL OF MILK PRODUCTS 



from 3.75 to 4.75 per cent, the decrease in the ratio is only 0.02 ; 

 and between 4.75 and 5.00 per cent, the decrease is only 0.01. 

 This is explained by the well-known fact that, in the case of 

 milk rich in fat, a smaller proportion of the fat is lost in cheese- 

 making than in the case of milk poorer in fat." 



The difference in value of milk with different percentages of 

 fat for the purpose of cheese-making should be fully recognized 

 both by the cheese-factory operator and by the milk producer, 

 and the price paid for milk should be in proportion to its value 

 for cheese-making. 



In considering the influence of milk quality on its value for 

 cheese-making, it should always be borne in mind that in addi- 

 tion to the greater yield from the milk rich in fat, there is also 

 an increase in the market quality of the cheese. Other things 

 being equal, cheese made from milk fairly rich in fat will be of 

 higher flavor and finer texture and will bring a better price 

 on the market. 



In regard to the solids lost in the whey in the process of 

 making cheese, Van Slyke 1 says : 



"Fat is present in milk in the form of very minute globules. 

 So small are these fat globules of milk that 5000 of them of 

 average size, laid side by side, would reach only one inch. 

 These are all scattered through the milk in enormous numbers. 

 Now, when the rennet causes the casein throughout the whole 

 mass of milk to solidify or coagulate, the fat globules are re- 

 tained or imprisoned in the solidified mass just where they were 

 at the instant that coagulation took place. When the curd- 

 knife passes through the mass, immense numbers of the mi- 

 nute fat globules are exposed on every cut surface and numbers 

 of these fall into the whey and are not retained in the cheese. 

 The more finely we cut the curd and the more violently we 

 handle the cut pieces of curd, the larger will be the number of 

 fat globules that go into the whey. 



1 New York State Experiment Station, Bulletin No. 68. 



