Effects of surimi by-product hydrolysates on processing quality and difference analysis of volatile compounds of silver carp surimi gel

The aim of this study was to investigate the effects of surimi by-product hydrolysates (SBPHs) on the processing quality, gel characteristics, microstructure, and volatile compounds of surimi. The results showed that the addition of SBPHs improved the water holding capacity (95.18% and 94.32%), texture property, and gel characteristic (546.04 g cm) of the surimi gel, reduced the cooking loss (7.15%) and aperture area (34.10%) of the surimi gel ( P < 0.05), causing no difference in their whiteness ( P > 0.05). The SBPHs reduced the free water and increased the immobilized water of the gel. At the same time, SBPHs made tighter cross-linking of the surimi gel proteins. The results of gas chromatography-ion mobility spectrometry showed that 62 volatile flavor compounds were detected in each group of surimi, and the relative contents of aldehydes, alcohols, and ketones were relatively high. A total of 19 volatile flavor compounds were selected as the potential markers in samples by orthogonal partial least square siscriminant analysis. The additions of SBPHs (0.6% and 1.2%) in this study were much lower than those of commercial cryoprotectant (6%). In conclusion, SBPHs emerges as a potential cryoprotectant for the surimi industry and have promising advantages in enhancing the quality of surimi. • Surimi by-products protein hydrolysates (SBPHs) remarkedly reduced the cooking loss and aperture area of surimi gel. • SBPHs reduced the free water and increased the immobilized water in the surimi. • SBPHs enhanced the flavor and texture of surimi gels. • A total of 19 volatile flavor compounds were selected as the potential markers in samples by OPLS-DA.