2O6 BACTERIA IN BUTTER. 



ever, that the flavor of the butter is somewhat improved, at 

 least for those markets that demand a clean, mild, acid flavor 

 to the butter and do not desire the more highly flavored 

 product which is characteristic of the American markets. 



Pure Cultures Compared with Natural Starters. A very 

 good natural starter is equal to and sometimes possibly 

 superior to the commercial cultures furnished by bacteriol- 

 ogists. At all events, where the matter has been tested it 

 is found that the .results obtained from the use of na- 

 tural starters, at least in America, rank equal with those 

 obtained from commercial cultures, and in some experiments 

 are somewhat superior. Moreover, the natural culture is 

 inexpensive and has the manifest advantage of being capable 

 of preparation by any ordinary butter-maker ,who has at 

 his command a clean dairy. On the other hand it re- 

 quires more time and trouble to .prepare a natural starter 

 than it does to use one of the commercial cultures, and in a 

 large creamery the extra care and trouble required for 

 the frequent preparation of natural starters is more than 

 sufficient to compensate for the slight expense of purchasing 

 the commercial products. Moreover, a natural starter cannot 

 be relied upon so strictly as can the commercial culture. In 

 the early years the commercial products*were liable to be 

 impure, since bacteriologists had difficulty in furnishing cul- 

 tures of bacteria that were not contaminated with other un- 

 desirable organisms. These difficulties, however, have been 

 overcome and the commercial cultures which may now be 

 purchased can almost always be relied upon as pure. If they 

 are pure cultures their action may always be relied upon as 

 being strictly uniform. Natural starters cannot be thus 

 relied upon. It is true that, in the majority of cases, if the 

 milk is obtained and allowed to sour under proper conditions, 

 the result will be a good, properly soured milk, which will be 

 an ideal natural starter ; but it is equally true that sometimes 

 such a result does not appear. Some dairies will be impreg- 



