RIPENING THE MILK. 153 



able, digestible, and concentrated form as much as 

 possible of the solids of the milk. The two chief 

 solids made use of are fat and casein. The other 

 solids of milk nearly all pass off in the whey. Only 

 about one-half of the total milk solids are available 

 for cheesemaking. The remainder is almost wasted, 

 which seems a great pity, as they are most valuable 

 food constituents. 



RIPENING THE MILK. 



The first step in the making of cheese is the ripen- 

 ing of the milk to such a point before adding the 

 rennet that the curd will be ready to " dip," /. e., have 

 sufficient acid for removal of the whey, in about two 

 and a half or three hours. Ripening consists of the 

 development of lactic acid in the milk, and by secur- 

 ing the same degree of ripeness each day the cheese 

 are more uniform, and the maker knows more 

 definitely how " the milk will work." Formerly the 

 ripeness of the milk was measured by means of a 

 rennet test, the first of which was devised by the late 

 J. B. Harris. It consisted of a cup of milk at a tem- 

 perature of 86 degrees, to which a teaspoonful of 

 rennet was added. The rennet was quickly stirred 

 into the milk and the time in seconds required for 

 coagulation was noted. As cups and spoons vary 

 considerably in size, something more accurate was 

 found necessary. An eight-ounce measuring glass for 

 milk and a drachm measure for the rennet was the 

 next improvement. The milk, at a temperature of 86 

 degrees, has a drachm of standard rennet extract added 



