SOME OF THE CAUSES AND THEIR PREVENTION 337 



not been reduced, and that in almost every case the butter was 

 fishy when it came out of storage. He said that as a result of 

 this he had made up his mind never to buy any butter from the" 

 so-called centralized creameries. The same firm now prefers to 

 buy butter for storage purposes from large creameries where the 

 acidity of the cream is reduced or controlled. 



The following is a quotation from U. S. Bulletin by L. A. 

 Rogers, S. C. Thompson and J. R. Keithley, page 8: 



" In a tabulation of the examination of 259 samples of 

 experimental butter from cream of known acidity, of 137 sam- 

 ples from cream having an acidity below 0.3 per cent, only 2, or 

 1.5 per cent, were marked ' fishy/ while of 122 samples having 

 an acidity of 0.3 per cent or over, 60, or 49.2 per cent, were fishy. 

 However, in all results which are dependent on the sense of 

 taste, allowance should be made for difference of opinion and in 

 the conception of the flavor associated with any particular 

 designation." 



U. S. Department of Agriculture Bulletin 84, page 23, 1906, 

 by C. E. Gray and G. L. McKay, entitled " The Keeping Qual- 

 ities of Butter made under Different Conditions and Stored at 

 Different Temperatures," would indicate that acid has a pro- 

 nounced effect in producing fishy flavor in butter unless the 

 acidity of the cream has been reduced by partial neutralization. 

 In this investigation part of the butter was made at Topeka, 

 Kansas, from sour cream. Other lots were made at Monticello, 

 Iowa, from sweet or whole-milk cream. The butter made from 

 sweet cream did not turn fishy in storage, while practically all 

 the butter made from sour cream had a pronounced fishy flavor 

 after being kept in storage for some time. 



Fishy flavor may be prevented with certainty by making 

 butter from pasteurized sweet cream. Butter made from pas- 

 teurized sweet cream with a starter added, but without ripening, 

 seldom if ever becomes fishy. 



Of 25 different churnings of cream made at Strawberry Point, 

 Iowa, July, 1907 (Bulletin 101, by McKay and Bower, page 164), 

 8 were made from unpasteurized cream and 17 from pasteurized 

 cream. The cream was ripened in all cases with a pure culture 



