MILK AND YIELD OF CHEESE 



197 



contain the milk-casein, which, as we have seen 

 (p. 145), has the power of neutralizing considerable 

 alkali, and of acting in this way like an acid. The 

 percentage of sugar in whey depends upon the time 

 when the whey is tested, the sugar decreasing in 

 amount as it is changed into lactic acid. 



In closing this discussion of the losses of milk 

 constituents in cheese-making, we give below tab- 

 ulated results of work showing the composition of 

 whey as obtained at cheese-factories in New York 

 through the work of the New York experiment 

 station. 



COMPOSITION OF CHEESE-FACTORY WHEY 



The following figures show the extreme variations 

 in the constituents of whey during the period of 

 investigation : 



