272 SCIENCE AND PRACTICE OF DAIRYING. 



conditions, for every 100 kg. of milk made into cheese, there 



are 5 to 7 kg. less of whey than in the case of hard cheeses. 

 The loss in cheese-making per 100 kg. of milk is, on a wide average, 



about 3 kg., not including the loss which arises in the ripening 



process. 



128. The Chemical Composition and Analysis of Cheeses. Cheeses, 

 both such as are destined to be consumed fresh, as well as those 

 which are allowed to ripen before consumption, are highly valuable, 

 and to a large extent also, favourite articles of food. In the first 

 place, they are rich in nitrogenous bodies. According to the method 

 of preparation and the age, they contain between 18 and 50 per 

 cent, on an average from 25 to 30 per cent, of nitrogenous matter. 

 In addition, from 2'5 to 46 per cent of fat, and a not inconsider- 

 able amount of mineral constituents, containing much phosphate 

 of lime, are found in them. The kilogram of nitrogenous substance 

 in cheese, more especially in skim-milk cheese, may be said to be 

 cheaper than in almost any other article of food. Skim-milk cheeses 

 are, however, as a rule, less pleasant in flavour and less digestible 

 than fat cheeses. Emmenthaler cheese, which is easily digested, and 

 of a fine mild flavour, satisfies all demands as a good suitable food. It 

 is on this account eaten with bread alone, or with bread-and-butter, 

 in larger quantities at one time than is the case with other cheeses. 

 A not inconsiderable number of the different kinds of cheeses are 

 used more as a bye-meat or appetizer than as an article of food 

 for satisfying hunger, or as the chief constituent of a meal. 



The chemical investigation of ripe cheese is a very difficult 

 operation, which can only be imperfectly carried out, owing to the 

 decomposition products which arise from the albuminoids and the 

 fat during ripening, too little being known to permit of their being 

 easily distinguished and their percentage exactly determined. All 

 the complete analyses of ripe cheese at present available, with the 

 exception of a few of the more recent researches, give merely a supej> 

 ficial and very unsatisfactory idea of the composition of cheese. In 

 these analyses, what is designated as fat is the entire amount of body 

 which has been extracted by ether or other fat solvent, regardless of 

 whether it consists wholly of fat or not. The percentage of protein, 

 or caseous matter, is generally expressed by a number obtained by 

 multiplying the percentage of nitrogen found with a constant 

 factor, viz. 6*25, which in the case of caseous matter is probably not 

 once right. A determination of this kind is of little value, even 



