The Nutritive Value of Yeast Protein.*

The idea of the use of yeast as a source of food protein for man and the higher.animals is not a new one; it has, however, been given renewed emphasis by the exigencies of the food situation during the war. Yeast is a highly nitrogenous by-product of the fermentation industries which heretofore has been largely wasted. It also presents the possibility of a synthetic production of protein from exceptionally simple compounds independent of seasons and crops. More recently the remarkable efficacy of the ordinary yeasts used in the manufacture of alcoholic beverages and also in bakeries in supplying water-soluble vitamine has been demonstrated.’ This property must be regarded as something apart from the nutrient value of the yeast protein as such. In the case of both adult men and animals the utilization of the nitrogenous components of yeast as judged by the “coefficient of digestibility” and the nitrogen balance has repeatedly been reported as good, although the statements on this point are not