石油酵母の脂肪について(第1報)

Abstract

The nutritive value of yeast grown on hydrocarbon substrates has been investigated. It seems that the estimation of the nutritive value of yeast differs according to the methods of chemical analysis. The analysis of fat in yeast is particularly questionable. An attempt was made to examine acid hydrolysis and ether extraction statistically, and to fractionate the fats. With this method and other methods, the amount of ether extract in yeasts was determined. The results were as follows: 1. It was found that the condition with A1 B2 C2 D2 E2 F2 made the amount of ether extract maximum (listed in Table 1 and 2). And its expected value was 14.75%. 2. The amount of ether extract by both modified AOAC method and (1) method was from four to six times as high as that by the official method. It seems, therefore, that acid hydrolysis or another treatments should be made before extracting fat. The ether extract by (1) method which showed the highest value was fractionated into non-fat substances 15_??_25% and true-fat 75_??_85%. Thus it was found that a considerable amount of impurity was contained in the ether extract.