MICROBES IN CHEESE-MAKING. 151 



their growth is entirely prevented by a thorough salting and washing 

 of the surface. In such cheeses the mold may grow within the 

 mass, but not on the surface. Whichever method is used, however, 

 the cheese is presently removed to the so-called 'cheese cellar' for its 

 proper ripening. These cellars may be cool, damp rooms, or caves, and 

 the flavor of some kinds of cheeses is largely due to the nature of the 

 caves in which the subsequent ripening is carried on. In these cellars 

 there is a constant but not very high temperature, and the atmosphere 

 is generally damp. Since the temperature and the moisture are kept 

 as constant as possible during the whole year, the cheese ripening can 

 continue slowly and indefinitely. To a considerable extent differences 

 in the ripening of soft cheeses are due to the different temperatures 

 of the cheese cellars, and this determines the kind of plant life that 

 shall flourish in this soft, nutritious food. 



After the removal to the ripening chambers, a new series of changes 

 begins in the cheese, due to new kinds of plant life. But as yet neither 

 the cheese-maker nor the bacteriologist, who has studied the matter 

 most carefully, can tell us much of the nature of the actual changes 

 which occur during this ripening. When the cheese is placed in the 

 ripening chamber it is certain that the growth of the molds is largely 

 stopped, and it is also certain that here begins a growth of a new class of 

 plants which we call bacteria. This moldy cheese, rendered alkaline by 

 the growth of the molds, furnishes a favorable medium for the 

 growth of different species of bacteria. At high temperatures they 

 would speedily decompose the mass, even to extreme putrefaction, but 

 at the low temperatures of the cheese cellars a complete putrefaction 

 does not occur. Bacteria growth takes place probably in all soft cheeses, 

 and as a result the nature of the cheese is profoundly modified. 

 Numerous new chemical products make their appearance, either as by- 

 products of decomposition or as actual secretions from the growing bac- 

 teria and molds. These new products have strong tastes and odors which, 

 as they slowly develop, gradually produce the characteristic flavor of 

 the ripened cheese. If the ripening continue long enough the decompo- 

 sition grows too advanced even for the strongest palate. But when the 

 proper ripening has been acquired and the tastes and flavors are of the 

 desired character, the cheese is sent to market, highly flavored by the 

 joint action of the bacteria and molds. It is still soft and moist, and the 

 ripening process continues, so that the cheese will not keep good for a 

 very long time. But while it is in the proper condition it furnishes the 

 educated palate with a flavoring product of great intensity, and most 

 highly relished by the numerous lovers of soft cheeses. 



While such is the general method of manufacture of the soft cheeses, 

 it must be recognized that the details of the manufacture differ widely. 

 Differences in the kind of milk used, whether whole milk, skim milk, 



