18 BOARD OF AGRICULTURE. 



matter, making the cheese appear rich in fats. This degenera- 

 tion of albuminoids into fatty matter always occurs in well- 

 ripened cheese. A similar change goes on in the bodies of 

 animals. It is well known, that a part of the album inous 

 matter consumed by animals may be converted into fat, and 

 the fat used as a supporter of respiration. Just how this 

 change is produced in the bodies of animals is not clear, but 

 the formation of fatty matter in cheese is the result of 

 fermentation, as certainly as fusil-oil is a result of alcoholic 

 fermentation. 



One of the ferments which the lacteal glands throw into the 

 ducts in their secretions has a digestive agency similar to 

 that in the later stages of its action in the conversion of milk 

 into ripe cheese, and also something of its earlier action, for 

 when it is abundant, it coagulates milk the same as rennet, 

 and at all times it has the effect of forming in the milk a 

 strong smelling oil, so light as to be volatile at sixty degrees. 

 This oil is the cause of the peculiar odor of new milk, and 

 also that of tainted milk. Its formation in milk is constant, 

 both before and after it is drawn, when temperature and 

 other circumstances will allow. The souring of milk, even, 

 does not stop it, but when it stands open to the air, being 

 volatile at a low degree, it passes off into the atmosphere as 

 fast as it is formed, and is not perceived, except when its 

 formation is very rapid, as in tainted milk. 



Tainted milk, in all its varying conditions and varieties, 

 has its origin in this oil, or the ferment from which it origi- 

 nates. The part which it plays in tainted milk has been 

 proved by covering a vessel of new milk and agitating the 

 vessel occasionally till the milk was tainted and strongly 

 charged with offensive odor. The oil was then collected by 

 distillation of the milk, and examined. It was perfectly 

 limpid and inodorous at and near the freezing point, but upon 

 warming a little it passed away quickly with all the offensive 

 odor of tainted milk. 



The effect of this newly discovered oil in dairy practices is 

 very great. It is a great stimulator of ferments. It hurries 

 up every species of fermentation w T hich occurs in milk, 

 cheese and butter. In milk, it not only occasions tainting, 

 but it hurries up souring, coagulation and decay. In cheese, 



