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This article focuses on the study of textural and protein characteristics of crisp grass carp (CGC) and grass carp (GC) fillets. The higher texture profile analysis (TPA) texture characteristics of CGC are related to a higher content of myofibrillar, sarcoplasmic, stromal proteins, sulfur amino acids and hydrophobic amino acids. Raman spectroscopy further revealed that the secondary and tertiary structural changes in the two fish meat proteins relate to the differences in TPA texture characteristics of the fillets. Lower α‐helix contents and higher β‐sheet contents are closely correlated to the special mastication properties of CGC fillets. More importantly, the disulfide bond content is another factor that affects the texture of CGC fillets. Furthermore, differential scanning calorimetry revealed that the special mastication properties of CGC fillets result from the greater stabilization afforded by proteins. Overall, the results show that the special texture characteristics of CGC fillet correlates positively with the protein characteristics found in fish muscle tissue. PRACTICAL APPLICATIONS Textural characteristics are an important quality for seafood products, which affects acceptability and mechanical processing of fillets. Crisp grass carps (CGCs), broadbean‐fed grass carp (GC), have special mastication. In previous studies, we have found that the differences of texture between both carp's muscles were highly significant. More importantly, the different texture correlated closely with their ultrastructures. Hence, CGC and GC muscles, as the objects for study, will be able to better reflect the relationship between texture and protein characteristics. The research aimed at revealing the mechanism of mastication in CGC muscle to resolve the mastication of CGC decreasing after freezing process.

The combination effect of high pressure (400, 500 and 600 MPa) and moderate heat (70 and 80C) on the inactivation kinetics and reduction of Bacillus coagulans spore in phosphate buffer and ultra‐high temperature (UHT) whole milk was investigated. The pressure come‐up time and corresponding logarithmic reduction of spore inactivation were considered during pressure‐thermal treatment. B. coagulans spore had a much higher resistance to pressure in UHT whole milk than in phosphate buffer. Survival data were modeled using the linear, Weibull and log‐logistic models to obtain relevant kinetic parameters. The tailing phenomenon occurred in all survival curves, indicating the linear model was not adequate for describing these curves. The mean square error and regression coefficient suggested that the log‐logistic model produced best fits to all survival curves, followed by the Weibull model. PRACTICAL APPLICATIONS It becomes increasingly apparent that high‐pressure treatment combined with moderate heat treatment for low acid and acid products is often required for effective bacterial spores' inactivation. Consequently, the prediction model of microbial survival curves is essential. Bacillus coagulans is a slightly pressure‐resistant and relatively heat‐resistant spoilage bacterium of considerable concern during the processing of acid foods. Spore inactivation effect during the pressure come‐up time is sometimes considerable and should not beignored. The use of mathematical models to predict inactivation for spores could help the food industry further to develop optimum process conditions.