CHAPTER X 



BACTERIA IN CHEESE 



ALTHOUGH cheese is, from a chemical standpoint, the most 

 nutritious of all of our foods, people do not usually eat it be- 

 cause they realiz.its nutritious value. It is eaten chiefly for 

 its flavor, since ityadds a relish to many another food that may 

 be flavorless. In' this respect its value is very great, for flavors 

 have a very important part in the economy of digestion. If we 

 look upon cheese, therefore, both from its nutritive and its 

 flavor value, we shall see that it is one of the most valuable 

 of foods. 



In making cheese the milk is usually first curdled with rennet, 

 after which the curdled casein is separated from most of the 

 water which drains from the curd as uhey. A large part of the 

 milk sugar is lost since it is dissolved in the whey, while most 

 of the fat remains entangled with the casein. About two-thirds 

 of the food material of the milk is thus retained in the cheese. 



The value of the cheese is largely dependent upon its ripening, 

 because it is this process which brings it into a proper condition 

 for eating. The fresh cheese contains all the original casein 

 of the milk, but it is rather hard, difficult of digestion and flavor- 

 less. The completed cheese is softer, easier to digest, and it 

 contains the desired flavor. 



RIPENING OF CHEESES 



The ripening of cheeses is a very complex phenomenon, and 

 one as yet only partly understood. This is due partly to the 

 intricacy of the subject, which has presented many difficult 



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