Continuous production of protein hydrolysates in immobilized enzyme reactors

Abstract

Abstract The digestion of several proteins, casein, α‐lactalbumin, human serum albumin and a mixture of whey proteins by immobilized pronase, thermitase and leucine aminopeptidase was studied on various conditions in five types of enzyme reactors. Reactors and operating conditions were designed to maximize the extent of hydrolysis and to minimize the adverse effects of the macromolecular nature of the substrates. A simple analytical method was developed to follow routinely the extent of hydrolysis. Substrate proteins were subjected to various pretreatments intended to disturb their native structure. The maximum feasible extent of hydrolysis in the reactor effluent, which is an average quantity, clustered around the magic figure of 33% in all systems studied. Protein digestion in bubbled column reactors charged with the polyaminomethylstyrene‐fixed thermostable proteinase “thermitase” and operated at 50 to 60°C turned out to be the most efficient setup to produce continuously amino acid/peptide mixtures.