Mechanism of improving water-holding capacity of Nemipterus virgatus myosin gel by soy protein isolate-stabilized Pickering emulsion

Abstract

The water-holding capacity of surimi gel is the main factor affecting the quality and economic value of surimi-based products. We here investigated the effects of varying concentrations (0%–10%) of soy protein isolate-stabilized Pickering emulsion (SPE) on gel properties, water-holding capacity, microstructure, and protein–water interactions of myosin gel. Adding SPE (2.5%–7.5%) enhanced the formation of hydrogen bonds, hydrophobic interactions, and disulfide bonds, thus augmenting gel strength and immobile water content. Based on capillary theory, crosslinking between SPE and myosin promotes the formation of a denser, more hydrophilic gel network, thereby improving capillary pressure to retain water. Isotopic H/D exchange unveiled that SPE modified the gel's microenvironment, thereby enhancing interactions between the gel and water. SPE boosts water-holding capacity by improving the gel network structure to elevate capillary capacity and altering the myosin structure to enhance its interaction with water.