266 MODERK DAIRY PRACTICE. 



The curing consists of a series of different fermenta- 

 tions which succeed one another and are caused by dif- 

 ferent kinds of bacteria appearing one after the other. 

 Duclaux first gave a scientific account of this phenomenon 

 in his in several respects remarkable work on milk entitled 

 "Le Lait, Etudes Chirniques et Microbiologiques." In the 

 Cantat cheese, manufactured in southern France, he found 

 not less than ten different kinds of bacteria during its period 

 of curing, seven of which were aerobic and three ana- 

 erobic. The statement made of the action of the different 

 bacteria is briefly as follows : Some of the bacteria pro- 

 duce both a rennet-like substance, the object of which is 

 unknown, and a ferment which changes the casein to a 

 soft consistency characteristic of the ripe cheese. Other 

 bacteria continue the work of the curing and give rise to 

 strong-smelling, often sharp fermentation products, which 

 finally may be still further changed by other bacteria and 

 decomposed into leucin, ammonia, etc. Weigmann has 

 also isolated this ferment (casease) and shown its great 

 importance in the curing of the cheese. 



Adametz investigated Swiss cheese (Emmenthaler) and 

 Swiss cottage cheese (Hauslcdse) belonging to the soft 

 kinds of cheese to be considered later on, and found in 

 them an enormous number of bacteria, of nineteen dif- 

 ferent forms, which he refers to three separate groups. 

 The bacteria of the first group are not able to dissolve the 

 casein, but change it to a characteristic jelly-like consist- 

 ency which later is easily attacked by other bacteria and 

 subjected to farther changes. Micro-organisms of the 

 second group continue where the first group left off and 

 are unable to attack the original curd. The bacteria of 



