PART V.* 



CHEESE. 



CHAPTEE I. 

 BACTERIA AND CHEESE-MAKING. 



CHEESE is coagulated and pressed casein which has 

 undergone certain processes of fermentation. Without 

 fermentations no cheese; without bacteria no fermenta- 

 tions; therefore without bacteria no cheese. The bacteria 

 make cheese out of the casein and give it the characteristic 

 flavor desired in each case. We owe the proof of the cor- 

 rectness of these statements to the bacteriological investi- 

 gations conducted during late years. Before 1875 it was 

 believed that the ripening of the cheese was a chemical 

 process. Cohn first maintained that this view was incor- 

 rect, and that the ripening is attributable to the vital pro- 

 cesses of all kinds of bacteria. Decisive proofs have later 

 been furnished by Duclaux, Schaffer, Bondzynski, and by 

 Adametz. 



The processes of fermentation which occur in the 



* Author's addition to American translation. 



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