Resumen de Germination‐Assisted Enzymatic Hydrolysis Can Improve the Quality of Soybean Protein

Hui Yang, Xin Li Ke Zhou, Jinyan Gao, Ping Tong, Anshu Yang, Hongbing Chen

• This study aimed to investigate the effects of combined germination and Alcalase hydrolysis on the quality of soybean protein. Protein profiles, water solubility, foaming and emulsifying properties, thixotropic properties, and in vitroprotein digestibility (IVPD) were tested, the chemical score (CS), essential amino acid index (EAAI), and protein efficiency ratio (PER) of soybean protein were also defined. The combined treatment of germination and Alcalase hydrolysis remarkably improved the solubility, emulsification activity index, emulsion stability index, and foaming capacity of soybean protein. Notably, a decrease in foaming stability was detected. The electrophoretic profile showed a weak breakdown of soybean protein during germination. However, a strong breakdown of protein was observed after the hydrolysis with Alcalase. The combined treatment also decreased the CS and EAAI of soybean protein, but only by 18%. Meanwhile, the IVPD and PER of soybean protein were significantly improved. Moreover, the protein of the germinated and hydrolyzed soybean flour demonstrated better swallowing properties. These findings indicated that the combined treatment of germination and enzymatic hydrolysis can improve the quality of soybean protein. Pretreatment of protein prior to enzymatic hydrolysis may lead to protein unfolding and increased enzyme accessibility to peptide bonds. Germination is an inexpensive and effective method to improve the nutritional quality of soybeans. A combination of germination and enzymatic hydrolysis may emerge as a new strategy for soybean food processing, resulting in a more prominent effect on the quality of the hydrolyzed soybean protein.