Controlling the co-aggregation and gelation of cod-soy binary proteins based on partially/fully denatured soy proteins

Food Chem. 2024 Nov 6;465(Pt 1):141931. doi: 10.1016/j.foodchem.2024.141931. Online ahead of print.

Abstract

Structured binary protein networks offer a pathway for designing gel-based foods with less ecological and economic effects. This study investigated the heat-mediated interaction and gelation kinetics of cod-soy mixed proteins at molecular level. Results indicated that denaturation degree of soy proteins was fundamental in determining the protein-protein interactions during heating. Considerable non-natural β-sheet was generated in the heterogeneous structures to initiate their aggregation behavior. Cod actomyosin comprising myosin heavy chains and actin mainly regulated their aggregation below 70 °C. At higher temperatures, the formation of large-sized and intermediary-sized aggregates was dominated by disulfide bond exchange between cod actomyosin and soy A-B aggregates (≤ 85 °C) or dissociated B subunits (> 85 °C). These aggregates were further evidenced as essential components to form gel networks with higher storage modulus (G'). These findings provide fundamental insights for designing gel-based products with desirable nutritional and textural properties based on plant-animal binary proteins.

Keywords: Diagonal SDS-PAGE; Heat-induced gelation; Molecular level; Protein-protein interactions; Soy protein; Water-soluble cod protein.