Assay of Biologic Value of Milk Proteins by Liver Xanthine Oxidase Determination
I. Powdered Products
Mei Yu Dju,
L. S. Baur and
L. J. Filer, Jr.
Ross Laboratories, Columbus, Ohio
1. Because the biologic value of milk proteins in diets preparedfor infant feeding that resemble human milk in composition isdifficult to evaluate by nitrogen balance methods in the rat,an indirect approach to the resolution of this problem was soughtin the measurement of liver xanthine oxidase activity.
2.Whole egg protein and milk proteins, as processed for powderedinfant foods, fed to rats either protein-depleted or transferredfrom a stock diet, give liver xanthine oxidase values in keepingwith known biologic values reported for these two types of protein.