Microwave sterilization is a novel potential sterilization technology to improve food quality. An industrial microwave sterilization system was used to sterilize imitation crab meat under thermal processing intensity F₀ = 1, 2, 3. The characteristics of the microwave process, such as heating rate, processing time, and C₁₀₀, were calculated. In addition, the quality of processed imitation crab meat was investigated. Compared with the conventional retort method, microwave sterilization significantly shortened the processing time of imitation crab meat by 63.71% to 72.45%. Under the same thermal processing intensity, microwave sterilization has demonstrated better results than retort sterilization in terms of water-holding capacity, color, and texture. Furthermore, microwave-treated imitation crab meat ingredients had a greater capacity to bind water molecules and obtained a more appropriate secondary protein structure. In addition, microwave technology can better preserve the unsaturated fatty acids (UFA) of imitation crab meat, which are 9.14%, 1.19%, and 0.32% higher than the traditional method at F₀ = 1, 2, 3. The results would provide useful data for the subsequent research and development of ready-to-eat surimi products.

Northern pike (Esox lucius) myofibrillar protein (MP) forms inherently weak gels due to endogenous proteolytic activity and the low thermal stability of fish myosin, limiting its application in surimi products. This study investigated the reinforcing effect and underlying mechanism of rice protein amyloid fibrils (RFs) on pike MP gels. Dynamic rheology revealed that RFs increased both the storage and loss moduli in a concentration-dependent manner, with the 5% group exhibiting an approximately threefold increase in the G′ at 100 rad/s relative to the control. The gel strength, hardness, and chewiness increased progressively with the RF content, whereas the water-holding capacity peaked at 1–3% RFs and declined sharply at 5% RFs. Microstructural imaging showed that moderate RF levels promoted a dense, homogeneous network architecture, while excessive RFs induced phase separation and structural heterogeneity. Hydrophobic interactions and hydrogen bonds were strengthened via RF incorporation, while disulfide bonds decreased monotonically with the increasing fibril concentration. FTIR spectroscopy revealed an α-helix-to-β-sheet transition, with the β-sheet content reaching a maximum of 49.37% at 3% RFs, and SDS-PAGE confirmed that the RF–MP interactions were predominantly non-covalent in nature. These results demonstrate that RFs reinforce pike MP gels through a molecular mechanism involving rigid fibrils acting as structural scaffolds within the protein network and a progressive shift from disulfide-mediated covalent crosslinking toward non-covalent stabilization via hydrophobic interactions and hydrogen bonding. The 1–3% RF range delivers the most balanced gel properties, while excessive fibril loading at 5% induces over-aggregation and impairs water retention. These findings establish amyloid fibrils as effective structural modifiers for freshwater fish gel products and provide a mechanistic basis for their application in surimi processing.

This study focuses on the selection of hybrid combinations of Hu sheep and meat quality analysis. A comparative analysis of meat quality and volatile flavor compounds was conducted using three hybrid groups—Australian White–Hu (AH), White Suffolk–Hu (SH), and Southdown–Hu (NH)—and a pure Hu sheep group (HH) as research subjects. The results show that in terms of basic nutritional quality, the moisture content in the NH group was significantly higher than that in the HH group (p < 0.05), and the crude protein content in the NH group was significantly higher than that in the HH group (p < 0.05). Regarding physicochemical properties, the NH group had significantly higher meat color scores, L*, a*, and b* values, than the other groups (p < 0.05), along with the best tenderness and cooking yield. An analysis of amino acids, fatty acids, and volatile flavor compounds in lambs from different hybrid combinations revealed significant differences in the contents of lys, thr, asp, and his (p < 0.01). Although no significant differences were found in the fatty acid composition scores among the AH, SH, NH, and HH groups, all groups met the FAO/WHO recommended values. The NH group not only had the highest MUFA and total fatty acid content but also the highest levels of trans-petroselinic acid and trans-vaccenic acid, the two most abundant trans fatty acids. A total of 43 volatile organic compounds were detected in the four groups, among which 10 were identified as differential compounds. This study provides a scientific basis for the hybrid utilization of Hu sheep and offers technical support for the transformation and upgrading of the regional meat sheep industry.

This study aimed to elucidate the characteristics of protein changes and their relationship with physicochemical properties during the quality deterioration of refrigerated Northern Pike (Esox lucius). We employed tandem mass tag (TMT)-based quantitative proteomics, combined with physicochemical indicators, including surface hydrophobicity, carbonyl content, sulfhydryl content, and myofibrillar fragmentation index (MFI), to systematically analyze protein alterations during cold storage. The results showed that with prolonged cold storage, the surface hydrophobicity, carbonyl content, and MFI of Northern Pike samples exhibited an increasing trend, whereas the sulfhydryl content decreased. Proteomic analysis identified a total of 563 differentially expressed proteins (DEPs) between fresh and cold-stored states, of which 293 were upregulated and 270 were downregulated. Furthermore, by integrating COG/KOG functional classification, subcellular localization, and GO enrichment analysis, the functional characteristics of the DEPs and their potential involvement in biological processes were systematically characterized. Correlation analysis revealed that six DEPs were significantly correlated with the changes in physicochemical indices of Northern Pike during cold storage, namely fructose-bisphosphate aldolase encoded by ALDOA, Nesh-SH3 domain-target protein, keratin, neurofilament heavy polypeptide, serine/arginine repetitive matrix protein 2-like, and asymmetrical bis(5′-nucleosidyl) tetraphosphatase. By integrating analyses of differentially abundant proteins and protein oxidation, this study suggests potential molecular mechanisms potentially responsible for quality loss in northern pike under chilled storage, offering a theoretical foundation for its preservation and quality assessment.