MILK PRODUCTS 329 



lower than in those made from whole milk, but no broad or 

 definite lines of division in the composition of the various 

 kinds of cheese can be recognised. In short, the chemical 

 composition of cheese is not characteristic of the type or 

 variety. 



On reference to the Table of Analyses on page 330, 

 it will be seen that, in many cases, there is a greater differ- 

 ence in the composition of two samples of the same kind 

 than in samples of different kinds. Such variations are attri- 

 butable, in large measure, to differences in the substance 

 from which the cheese is made. For instance, the ratio of fat 

 to casein is generally higher in Stiltons than in Gloucesters, 

 because the former are usually made from milk to which a 

 certain amount of cream has been added, and the latter from 

 partially skimmed milk. The fact must not be overlooked, 

 however, that either or both may be made simply from whole 

 milk, and the ratio of fat to casein might, therefore, be 

 practically the same in both. In that case, the characteristic 

 differences between the two types must be attributed wholly to 

 the differences in the method of treatment. 



It is impossible, therefore, to lay down any rigid classifica- 

 tion of cheeses on this basis, but the following is recognised as 

 customary, and will be found useful in interpreting the analyses 

 in the table : 



Original substance. Products. 



I. Cream .... English cream cheese, Gervais, 

 IL Milk and Cream . Stilton. 



(H d /American, Cheddar, Cheshire, 

 TTT -niTi- i MI [-tiara < Q rU y re Gorgonzola. 



III. Whole milk . . /Camembert, B?ndon, Brie, 



\ Limburg. 



IV. Skim milk . . . aCeSter> ^^ ParmeSan> 



The principal object of the various methods of treatment 

 to which the several kinds of cheese owe their distinctive 

 properties, is to control the fermentative changes which take 

 place in the process of ripening. These changes are, for the 

 most part, too complex and obscure for present discussion. 

 Apart from them, 4 the chemistry of the process by which a 



