Dairy Bacteriology. 



prevent those originally present in the cream from grow- 

 ing. 1 This repressive action of one species on another is a 

 well-known bacteriological fact, but it must be remembered 

 that such an explanation is only applicable in those cases 

 where the culture organism is better able to develop than 

 those forms that already exist in the cream. 



If the culture organism is added to raw milk or cream 

 which already contains a flora that is well suited to develop 

 in this medium, it is quite doubtful whether it would gain 

 the supremacy in the ripening cream. The above method 

 of adding a culture to raw cream renders cream-ripening 

 details less burdensome, but at the same time Danish ex- 

 perience, which is entitled to most credence on this ques- 

 tion, is opposed to this method. 



Reputed advantages of culture starters. 1. Flavor and 

 aroma. Naturally the flavor produced by pure-culture fer- 

 ments depends upon the character of the organism used. 

 Those which are most extensively used are able to produce 

 a perfectly clean but mild flavor, and a delicate but not 

 pronounced aroma. The u high, quick" flavor and aroma 

 that is so much desired in the American market is not 

 readily obtained by the use of cultures. It is quite problem- 

 atical whether the use of any single species will give any 

 more marked aroma than normally occurs in natural ripen- 

 ing. 



2. Uniformity of product. Culture starters produce a 

 more uniform product because the type of fermentation is 

 under more complete control, and herein is the greatest 

 advantage to be derived from their use. Even the best 

 butter-maker at times will fail to secure uniform results 

 if his starter is not perfectly satisfactory. 



1 Conn, 9 Storrs Expt. Stat, 1890, p. 25. 



