BACTERIA IN OLEOMARGARIN MANUFACTURE. 



which the butter-maker makes use of in manufacturing his 

 butter. The oleo manufacturer, in other words, uses the 

 decomposition products of bacteria growth obtained by a 

 method similar to that which is used in the manufacture of 

 butter. The method is commonly based upon a process some- 

 what as follows : 



A considerable quantity of milk, or sometimes cream, is 

 placed in proper vessels, which are kept at moderately warm 

 temperature and the milk is allowed to sour. Sometimes 

 ordinary milk is simply warmed and allowed to stand until 

 the lactic bacteria grow and sour it; in other cases, a lactic 

 starter is added to the milk. After the milk has been prop- 

 erly soured it is mixed with the fats in the mixing vats and 

 the whole product of the mixture is drawn off into brine. 

 The final hardened product thus consists of a mixture of the 

 various fats, together with a considerable proportion, about 

 one fifth, of real soured milk. The souring of the milk has 

 produced in it the same kind of decomposition products 

 which give rise to the flavors of butter, and consequently the 

 oleo product is impregnated with flavors .which cause it to 

 resemble butter. The same flavors are imparted to the oleo 

 as would be imparted to butter under similar circumstances. 



The oleo manufacturers fully understand that the secret 

 of obtaining a ready market for the oleomargarin is in obtain- 

 ing the desired flavors in their product, and they are also 

 fully aware of the fact that these flavors are given to them 

 by bacterial action. They, therefore, use the best methods 

 that they can devise for favoring the growth of the desired 

 organisms, for the purpose of developing the flavors. Ordi- 

 narily the milk used for the purpose is allowed to sour 

 by normal lactic fermentation; but in recent years some of 

 the oleo manufacturers have not been satisfied with this 

 rather uncertain method, and have endeavored, by scien- 

 tific means, to control the ripening of their milk through the 

 aid of pure cultures of bacteria. In some cases such manu- 



