Processing suitability of three tilapia species for alternative freshwater surimi: A comprehensive evaluation from muscle physicochemical to gelling properties

The unclear relationship between basic characteristics of cultured fish and processing suitability restricts the precise aquatic product processing. In this study, processing suitability of Red tilapia (Oreochromis spp.), GIFT (Oreochromis niloticus, Genetically Improved Farmed Tilapia) and Blue tilapia (Oreochromis aureus) species were evaluated based on the muscle physicochemical and gelling properties. The results showed that Red tilapia and GIFT tilapia had better muscle texture, nutrient balance and flavor characteristics. Correlation analysis showed that muscle multi-scale structure (hardness, myofibrillar diameter, segment length) and endogenous enzymes contents (Transglutaminase (TGase), cathepsin L) were the key factors regulating the gelling quality of surimi materials. The results of gel strength, Micro-CT and SEM showed that Red tilapia and GIFT tilapia surimi gel had a more dense three-dimensional network structure. In addition, the excellent whiteness of Red tilapia surimi makes it expected to become the alternative freshwater surimi for the fabrication of high-grade surimi products.