Acid Values and Acid Ratios as Related to the Keeping Quality of Salted Butter

Abstract

The acid content, calculated as lactic acid, and as determined in this investigation for 26 samples of sweet cream butter with pH values above 6.0 was 0.07−0.13 per cent when fresh, 0.072−0.145 per cent after 1 week at 21° C., and 0.079−0.131 per cent after 1 month at 0−5° C. It averaged 0.096 per cent when fresh, 0.109 per cent after 1 week at 21° C. and 0.103 per cent after 1 month at 0−5° C. For 51 samples of neutralized cream butter these averages were 0.122, 0.140 and 0.132 per cent, respectively. High acid values of butter and butterfat before and after storage showed a slight tendency toward reduced keeping quality. High increases in the acid values after storage at 21° C. and 0−5° C. did show a fairly close correlation with reduced keeping quality of sweet cream and neutralized cream butter but especially of sweet cream butter. An increase in the acid ratio (fat acidity: butter acidity) during 1 week at 21° C. and during 1 month at 0−5° C. seemed to be closely related to poor keeping quality, especially in the case of sweet cream butter. The average acid ratios were higher after 1 month at 0−5° C. than after 1 week at 21° C. © 1940, American Dairy Science Association. All rights reserved.