Abstract:In order to improve the quality of frozen large yellow croaker, breeding large yellow croaker was selected for the project. Based on unpackaged air circulation freezing (UAF-0), vacuum film packaging air circulation freezing (PAF-1), the study compared the differences of freezing rate, physical and chemical properties of large yellow croaker between vacuum film packaging cold storage cycle freezing(PLF-1) and unpackaged refrigerant circulating freezing(ULF-0). The results showed that although the time for maximum ice crystal formation in the PLF-1 mode was 44 minutes longer than that in the ULF-0 mode, the myofibril microstructure of large yellow croaker was relatively clear, the muscle tissue damage and chromatic aberration change were relatively small, and hardness, elasticity, chewiness and recovery were only decreased by 6.8%, 1.2%, 1.2% and 1.9%, respectively. Neither the change of pH nor the decrease of salt soluble protein content was obvious( P >0.05), the rising rate of TVB-N was the slowest. Comparing the large yellow croaker quality of four freezing methods, the following was the order from good to bad: PLF-1>ULF-0>PAF-1>UAF-0.
