DIVERSITY 



Bacteria in Butter- Making. 145 



B. BACTERIAL DEFECTS IN BUTTER. 



146. Lack of flavor. Often this may be due to im- 

 proper handling of the cream in not allowing it to ripen 

 far enough, but some times it is impossible to produce a high 

 flavor. The lack of flavor in this case, is due to the ab- 

 sence of the proper flavor- producing organisms. This 

 condition can usually be overcome by the addition of a 

 proper starter. The relation between flavor and desir- 

 able bacteria is very intimate, and troubles of this kind 

 usually arise, because the proper forms commonly found 

 in the cream have been supplanted by other species that 

 do not possess the ability of forming these aromatic sub- 

 stances so necessary in sour cream butter. 



147. Putrid butter. This specific butter trouble has 

 been observed in Denmark, where it has been thoroughly 

 studied by Jensen 1 . Butter affected by it rapidly ac- 

 quires a peculiar putrid odor that ruins it for table use. 

 Sometimes, this flavor may be developed in the cream 

 previous to churning. Jensen found the trouble to be 

 due to several different putrefactive bacteria. One form 

 which he called Bacillus fcetidus lactis, a close ally of the 

 common feces bacillus, produced this rotten odor and taste 

 in milk in a very short time. Fortunately, this organism 

 was easily killed by a comparatively low heat, so that 

 pasteurization of the cream and use of a culture starter 

 quickly eliminated the trouble, where it was tried. 



1 48 . Turnip-flavored butter. Butter sometimes ac- 

 quires a peculiar flavor recalling the odor of turnips, 

 rutabagas, and other root crops. Often this trouble is 

 due to feeding, there being in several of these crops, 

 aromatic substances that pass directly into the milk, but 

 in some instances the trouble arises from bacteria that 



1 Jensen, Cent. f. Bakt., 11: 409, 1891. 

 10 B. 



