Notes on a deamination method proposed for determining ‘chemically available lysine’ of proteins

Abstract

1. Details of a chemical method, using acetic acid and sodium nitrite, for determining ‘available lysine’ in plant materials are given. An analytical procedure was used which distinguished lysine from ornithine; the latter was liable to arise in the course of the deamination and hydrolysis procedure.2. The experimentally determined ‘available lysine’ contents of various samples of leaf-protein concentrates showed significant positive correlations with previously reported values for their biological value and true digestibility. ‘Available lysine’correlated significantly with total lysine liberated by direct acid hydrolysis.