RELATION OF BACTERIA TO DAIRY INDUSTRY. 87 



The cheese maker finds in the ripening of his 

 cheese the most difficult part of his manufacture. 

 It is indeed a process over which he has very 

 little control. Even when all conditions seem to 

 be correct, when cheese is made in the most care- 

 ful manner, it not infrequently occurs that the 

 ripening takes place in a manner that is entire- 

 ly abnormal, and the resulting cheese becomes 

 worthless. The cheese maker has been at an en- 

 tire loss to understand these irregularities, nor 

 has he possessed any means of removing them 

 The abnormal ripening that occurs takes on vari- 

 ous types. Sometimes the cheese will become 

 extraordinarily porous, filled with large holes 

 which cause the cheese to swell out of proper 

 shape and become worthless. At other times, 

 various spots of red or blue appear in the manu- 

 factured cheese; while again unpleasant tastes 

 and flavours develop which render the product of 

 no value. Sometimes a considerable portion of 

 the product of the cheese factory undergoes such 

 irregular ripening, and the product for a long 

 time will thus be worthless. If some means 

 could be discovered of removing these irregu- 

 larities it would be a great boon to the cheese 

 manufacturer; and very many attempts have 

 been made in one way or another to furnish the 

 cheese maker with some details in the manufac- 

 ture which will enable him in a measure to con- 

 trol the ripening. 



The ripening of the cheese has been subjected 

 to a large amount of study on the part of bac- 

 teriologists who have been interested in dairy 

 products. That the ripening of cheese is the 

 result of bacterial growth therein appears to be 

 probable from a priori grounds. Like the ripen- 



