A Study of the Ether Extract of the Materials Estimated as Fat in the Babcock Test of Milk

Abstract

1.In Babcock tests in which 15.0 ml. of sulfuric acid of specific gravity 1.82–1.83 were used the ether extract of the fatty materials aspirated from the bottle neck averaged 98.4653 per cent as compared with 98.1080 per cent when these materials were removed with the bottle necks.2.Higher estimations for fat by the Babcock method, but lower per centages of ether extract from the materials so estimated, were obtained with 17.5 ml. than with 15.0 ml. of sulfuric acid of specific gravity 1.82–1.83.3.Approximately 57 per cent of the acid impurities in the fatty materials in the Babcock “fat” column, were soluble in ether, as judged by the acid number of this material and that of its ether extract in comparison with the acid number of butter fat. Use of 17.5 ml. of sulfuric acid yielded larger amounts of acid impurities in the “fat” column than use of 15.0 ml.4.A reconciliation between the Babcock and Mojonnier methods on an ether extract basis yielded a difference of 0.1501 per cent in favor of the Mojonnier method.