New York Agricultural Experiment Station. 15 



department op baotbriology. 



The following work has been carried on by the bacteriological 

 department with the active cooperation of the dairy expert on 

 all points which called for a knowledge of practical conditions. 



Fishy flavor in milk. — An outbreak of this trouble was traced 

 to the milk of a single animal. This cow seemed in good health 

 but the milk possessed this intensely disagreeable flavor when 

 freshly drawn. By tainting all the milk with which it was 

 mixed the product of this one cow had caused a marked falling 

 off in the business of a city dealer. All trouble ceased when the 

 milk of this one animal was rejected. No biological cause for 

 the flavor could be discovered. 



Bitter flavor in Neufchatel cheese. — An outbreak of the trouble 

 in a factory was studied and found due to the activity of certain 

 kinds of bacteria. By making cheese from samples of the milk 

 of each patron the source of the trouble was located and re- 

 moved. 



Sweet flavor in CJieddar cheese. — Work upon this subject has 

 been continued throughout the year. It has been found that 

 while yeasts occur but rarely in clean-flavored cheese they are 

 regularly present in considerable numbers in all cheese selected 

 for our study by cheese experts as typical examples of sweet 

 flavor. This opens up an entirely new field concerning the rela- 

 tion of yeasts to bad flavors in cheese and work is being continued 

 along this line. 



Rusty spot in Cheddar cheese. — Reports seem to show an in- 

 crease in trouble from this source during the present year. The 

 bacterium causing the trouble was isolated from the product of 

 factories in three different counties and its action studied when it 

 was introduced into the cheese vat. When cultures of the germ 

 were mixed with the milk before adding the rennet, little dis- 

 coloration of the cheese resulted; but when introduced into the 

 vat after the curd was cut, the cheese became very red. 



This would seem to indicate that the time of introduction is 

 important, and that infection from the factory and utensils is a 

 more probable source of harm to the cheese than introduction 



