Digestibilities of the protein in various foods as determined in vitro by an immobilized digestive enzyme assay (IDEA).

The digestibility of the protein in various foods or food components was analyzed using an immobilized digestive enzyme assay (IDEA) system. The assay consists of two bioreactors, one containing pepsin and the other containing trypsin, chymotrypsin and intestinal mucosa peptidases. The fraction of the peptide bonds hydrolyzed during an extent of hydrolysis assay was correlated with independent in vivo determinations of the digestibilities. A correlation coefficient of 0.80 was obtained. The derived linear regression equation can be used to predict digestibility. The method is sensitive to structural modification of protein, as for example, those caused by effects of heat treatment.