Effect of enzymatic processing on the physicochemical properties of wheat gluten protein enzymatic products

Abstract Background and Objectives Wheat gluten is a high‐quality, low‐priced, and nutritious plant protein. Applications of wheat gluten protein could be expanded by improving its solubility through enzymatic modifications. Herein, we investigated the effect of proteolytic processing on the physicochemical properties of wheat gluten protein. Findings The degree of hydrolysis, trichloroacetic acid‐soluble nitrogen (TCA‐SN), and peptidyl nitrogen content of the enzymatic digestion products increased, and the TCA‐SN content exceeded 60% in all cases. The ζ‐potentials of all products after enzymatic digestion were significantly decreased and were negative. Three enzymatic solutions increased the stability of the solution system and the surface hydrophobicity of the enzymatic products to different degrees. The products after enzymatic digestion by alkaline protease had better antioxidant capacity. Conclusions This study provides theoretical support for expanding the applications for wheat protein to achieve the added value of wheat products and enhance the utilization rate of these readily available raw materials. Significance and Novelty This study investigates the dual enzyme stepwise enzymatic hydrolysis of wheat gluten protein by alkaline protease and neutral protease, which increases the water‐soluble protein content of wheat gluten protein. The resulting hydrolysate has a high peptide nitrogen content.