| Summary: | <b>Objective:</b> The effects of freezing method and storage temperature on the quality of large yellow croaker during storage were investigated. <b>Methods:</b> Fresh large yellow croaker fillets were frozen with dry ice and air freezing (-40 ℃) to the central temperature of -18 ℃, and then stored at -40 ℃ and -18 ℃, respectively. Physical and chemical indexes such as freezing curve, ice crystal morphology, pH value, volatile base nitrogen, K value, Ca<sup>2+</sup>-ATPase activity, total sulfhydryl group, carbonyl group, protein degradation and texture characteristics of large yellow croaks were determined after freezing and during freezing storage. <b>Results:</b> The time of dry ice freezing through the maximum ice crystal formation zone was 40 min, which is 1/6 of that of air freezing at -40 ℃. The initial ice crystal cross-section area and equivalent diameter of dry ice frozen fish samples were (96.12±1.61) μm<sup>2</sup> and (11.06±1.43) μm, respectively, which is significantly lower than that of air frozen fish samples. <b>Conclusion:</b> The effect of freezing temperature on fish myofibrillator protein was greater than that of freezing temperature, and a lower freezing temperature can result in a lower degradation degree of fish myofibrillator protein. Storage at -40 ℃ after dry ice freezing is beneficial to maintain freshness and quality stability of large yellow croaker.
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