Mechanism of phosphates modification on squid myofibrillar proteins and effect on gel properties of surimi

In this study, we investigated the effects of four phosphates on the structure of myofibrillar proteins and the gel properties of surimi. The results indicate that phosphate-modified proteins exhibit lower particle size, zeta potential, and surface hydrophobicity. Among them, sodium pyrophosphate (TSPP) and sodium tripolyphosphate (STPP) could depolymerize proteins, sodium hexametaphosphate could repolymerize proteins, and sodium trimetaphosphate enables proteins to partially reaggregate after dissociation. The addition of TSPP and STPP to squid surimi gel enhances hydrophobic interactions, improving protein cross-linking, thereby reducing the pore space of squid surimi gel and increasing gel strength, texture profile analysis (TPA) properties, and water holding capacity (WHC). This provides a reference for the use of phosphates during the processing of surimi products.