360 CHEESE 



milk. About one-half of the solids in the milk is 

 recovered in the cheese. The fresh curd is manipulated 

 in a great variety of ways, and from it a correspondingly 

 large number of kinds of cheese are made, differing in 

 size, form, texture, and other physical characters. The 

 different kinds vary considerably in chemical composition. 

 The firm or hard cheeses obtained by coagulation at 

 temperatures between 30 to 35 C. contain from 



28 to 35 per cent, of water, 



25 35 ^t, 



23 35 proteins, 



I 3 sugar, lactic acid, and 



2.7 ,,4 ash. 



The soft cheeses prepared from curd precipitated at 

 temperatures below 30 C. contain from 



45 to 50 per cent, of water, 



20 30 fat, 



1 8 20 proteins, 



and small amounts of sugar, lactic acid, and mineral 

 matter. 



Freshly made cheese is at first of a firm, elastic 

 texture, is slightly acid, practically insoluble in water, 

 indigestible, and possesses no very definite cheesy odour 

 or taste. Sooner or later, however, very extensive 

 physical and chemical changes occur within it, and the 

 cheese is said to ripen. Much of the insoluble material 

 becomes soluble and is then easily digested, at the same 

 time the different varieties of cheeses develop their own 

 peculiar characteristic aroma and flavour. The chemical 

 changes which take place during the ripening process 

 are very complex, and, in spite of much investigation, 



