2/O AGRICULTURAL BACTERIOLOGY. 



In practical cheese-making we do not yet find pure cultures 

 used to any extent. 



POSSIBILITY OF USING PURE CULTURES. 



It can readily be believed that there is a great future for the 

 cheese industry along the lines of the practical application of 

 bacteriological discoveries. The problem of cheese-ripening 

 is being eagerly studied by bacteriologists. The industry 

 involves great financial interests. The success of the cheese- 

 making depends upon the ripening. A large per cent, of 

 the cheeses made are greatly depreciated in value, or abso- 

 lutely ruined, by their failure to ripen properly. If it is pos- 

 sible to discover some method by which the ripening can be 

 controlled, so that the cheese-maker can be sure of its taking 

 place uniformly, it would mean a saving of millions of dollars. 

 Moreover, the development of the ripening methods would 

 greatly extend the industry. Some of the favorite cheeses can 

 be manufactured only in certain localities, a fact that has been 

 interpreted as meaning that these localities are especially im- 

 pregnated with the appropriate species of microorganisms 

 which are wanting in other localities. This is certainly true 

 in some cases, as is proved by the fact that it is possible to 

 start new factories in new localities by simply rubbing the 

 shelves of the cheese rooms, and the vessels of various sorts, 

 with fresh cheese from the factory where the product is nor- 

 mally developed. Such a procedure would, of course, inocu- 

 late the new factory with the organisms necessary to start the 

 normal ripening. 



If it were possible to learn more thoroughly the exact na- 

 ture of the microorganisms producing the desired flavors, it 

 would certainly be possible to extend the manufacture of 

 many types of cheeses far beyond their present homes. But 

 the subject is complex and as yet in the experimental stage. 

 Each type of cheese is a special problem which must he 



