MILK AND YIELD OF CHEESE 201 



and insoluble salts constitute one group, furnishing 

 most of the solid matter in cheese, and we can call 

 these constituents cheese-producing solids. On an 

 average, milk contains about 0.90 per cent of salts, 

 of which about 0.25 pound goes into cheese for each 

 100 pounds of milk and 0.65 pound into whey, vary- 

 ing, of course, with many conditions. The other 

 constituents of the milk-solids, the sugar, the albu- 

 min and the soluble salts, those constituents of the 

 milk that exist in true solution, pass largely into 

 the whey and are lost, except in so far as they are 

 held by the water or whey in the cheese. Their 

 amount in cheese will depend upon the amount of 

 whey retained in the cheese. Those solid constitu- 

 ents existing in solution in the whey we may prop- 

 erly characterize as whey-solids. This division of milk 

 constituents into cheese-producing solids and whey- 

 solids is, of course, not strictly accurate, because 

 small amounts of cheese-solids pass into whey and 

 small amounts of whey-solids are retained in 

 cheese. But, for the purpose of studying the gen- 

 eral relations of milk-solids to cheese, the classifi- 

 cation is close enough. The figures presented be- 

 low are largely taken from work done at the New 

 York experiment station, covering a period of four 

 years and are largely derived from actual cheese- 

 factory conditions. 



The cheese-producing solids were found to aver- 

 age 6.50 pounds, varying in extreme cases from 

 5.25 to 7.75 pounds for 100 pounds of milk, but the 

 greater portion of factory milk comes within the 

 narrower limits of 5.75 to 7.25 pounds. The whey- 

 solids of milk varied from 5.75 to 6.75 pounds and 



