Evaluation of Proteins by In Vitro Pancreatin Digestion

THE RATE of enzymatic digestion was reported by Melnick et al. (1946) to be of use in explaining why a given protein may show differences in its biological value after heat treatment, though its ultimate amino acid composition and degree of digestibility remain unchanged. Results obtained by Hankes et al. (1948) for the liberation of amino acids from raw and heated casein showed that the rate of release of alpha-amino nitrogen during pancreatin digestion is slightly increased by autoclaving for 4 minutes and decreased by autoclaving for 20 hours. The same conclusion was drawn by Riesin et al. (1947) from studies on raw, properly heated and over heated soya bean meals. In connection with the nutritive value of soya bean meals, the alpha-amino nitrogen released by enzymatic digestion was reported by Ingram et al. (1949) to have close agreement with the growth of chicks but in the case of …