Biological evaluation of legume proteins in combination with other plant protein sources

Abstract

The mutual supplementary effect of legume proteins and other food proteins was investigated with rats by determinations of the net protein utilization of mixtures in which increasing amounts of legumes were replaced by other protein sources. The nutritive values of the proteins and protein mixtures are presented in curves showing the occurrence or absence of a mutual supplementary effect and also the proportion of the proteins in the mixtures with maximum mutual supplementation. Comparable results from the literature are recorded in a similar way. Cereal proteins and legume proteins exert a considerable effect, resulting in values that exceed those of the proteins fed separately. No supplementation occurred in mixtures of potatoes and legumes. Sesame protein and to a lesser extent also sunflower-seed protein exerted a mutual supplementation with legume proteins. Animal proteins, like meat, fish and milk, showed no supplementary effect in combination with legume proteins. The effect was considerable in mixtures of legumes and whole egg or egg white. The influence of the limiting amino acid and of the relative excess of essential amino acids on the supplementary effect is discussed.