72 Agricultural Bacteriology. 



taste and odor of the milk. The milk may not have a 

 marked taste, while the butter prepared from it may 

 show the influence of the feed to a great degree, because 

 the fat absorbs the flavoring substances and thus they 

 are concentrated in the butter. It is practically impos- 

 sible to feed turnips, cabbage, and rape without the taste 

 of these vegetables appearing in the butter. Green 

 clover, strong silage, and various weeds which the cattle 

 may eat when the grass is short in the pastures may also 

 injure the butter. Butter brought in contact with pro- 

 nounced odors, such as that of bananas, will absorb 

 enough so that the flavor is very evident. This absorp- 

 tion by the fat may take place either before or after 

 churning. For this reason milk, cream, and butter 

 should be kept in a place free from all odors. Weig- 

 mann of Germany has found certain kinds of bacteria in 

 milk which impart to the butter a flavor like that of tur- 

 nips. 



" Fishy" butter is quite common causing in some 

 creameries a large loss. The true cause of this trouble 

 is not known with certainty. 



Moldy butter. The common molds, which appear so 

 quickly on bread, cheese, etc., do not as a rule cause trou- 

 ble in butter but certain other kinds of molds are es- 

 pecially troublesome. They develop mainly in the outer 

 layer of the butter, where they have access to the oxygen 

 of the air, or on the parchment paper or inner face of the 

 butter tub itself. 



