IQ4 BACTERIA IN BUTTER. 



troubled by the development of improper flavors and an 

 unsatisfactory type of butter. 



Control of Cream Ripening. The butter-maker has little 

 or no control over the kinds of bacteria which find their way 

 into his cream. This is especially true of a creamery that 

 receives cream from a wide territory ; for such a creamery 

 must take the cream that is brought, and this will be filled 

 with bacteria of numerous varieties derived from many 

 sources. If it chances that the cream which reaches the 

 creamery contains the proper species of bacteria, the ripen- 

 ing .will go on in a normal fashion and the results obtained 

 will be satisfactory. -If it chances, however, that the cream 

 brought to the creamery contains species of bacteria which 

 are unfavorable -to the development of proper flavors, the 

 butter is likely to fall off in quality, and no care which the 

 butter-maker may take in the subsequent preparation of his 

 butter can remedy this particular defect. 



It is, of course, quite evident that it will be an advantage 

 to have some method of controlling the growth of bac- 

 teria in the cream. The revolution which has been pro- 

 duced in the brewing industry by the use of pure yeast cul- 

 tures has led to the suggestion that a similar control might 

 be possible in cream ripening, which is also a fermentative 

 process, and that the whole process of butter-making would 

 be improved if a method could be devised of controlling the 

 growth of the organisms that produce cream ripening. 

 According to this idea bacteriologists have developed, in the 

 past fifteen years, a process of butter-making which has been 

 spoken of as the use of pure-culture starters. 



The Use of Starters. This process was suggested about 

 fourteen years ago by Professor Storch, of Copenhagen, who 

 first conceived the idea of obtaining from cream those species 

 of bacteria which produce the best results, and then furnish- 

 ing them to the butter-maker for the purpose of cream ripen- 

 ing, somewhat as yeast is furnished to the brewer (229). 



