Evaluation of gel properties of heat-induced surimi of Ictalurus punctatus from four genealogies

Ictalurus punctatus has less fishbones and more meat, very suitable for being processed into surimi products. In order to evaluate the processing characteristics of surimi of I. punctatus from different genealogies, we selected the dorsal muscle of the four genealogies of "Jiangfeng No.1" I. punctatus (DZ1-1, KB4-1, K2-1, 46-1) which were prepared into surimi after rinsing, chopping, dewatering and refined filtration, and heated them at two stages to make heat-induced surimi gels. By measuring the thermal stability of surimi protein, physical and chemical properties of the surimi gels, such as whiteness, texture, water holding capacity and gel strength, we analyzed the heat-induced gels of I. punctatus from different genealogies. The results show that compared with the other genealogies, the surimi myofibrillar protein of DZ1-1 genealogy had higher thermal stability, and the relative content of β-folding and β-turning structure was higher, which affected the gel quality of heat-induced surimi. There are no significant differences in the whiteness of heat induced surimi gels prepared by different genealogies of I. punctatus, with water holding capacity over 80%. The gel strength of the DZ1-1 genealogy was 2.7×10² g∙cm, which was better than other genealogies, while the hardness, springiness and gumminess of the DZ1-1 genealogy were not different from the KB4-1 genealogy, but significantly better than the other two genealogies. In conclusion, the DZ1-1 genealogy is more suitable for surimi processing.