Freezing temperature effects on quality of Larimichthys crocea

This study aimed to investigate the effects of freezing temperatures (-20 °C, -35 °C, -40 °C, -60 °C, and -80 °C) on the body color and muscle quality of large yellow croakers (mean weight: 354.88 ± 13.18 g), with chilled fish (0 °C) serving as the control group. A total of 150 fish were divided into 6 groups of 5 replicates of 25 fish each. The results showed that the -80 °C group exhibited total sensory scores, conductivity, pondus hydrogenii (pH) values, and thiobarbituric acid (TBA) values most comparable to the control group. Compared with the control group, the brightness (L*), red-green (a*), and yellow-blue (b*) values of the tail and back skin in the -60 °C and -80 °C groups showed no significant differences ( P > 0.05). Additionally, the total carotenoid contents in the abdomen and back skin of the -80 °C group were not significantly different from those of the control group ( P > 0.05). In terms of muscle texture, the hardness, cohesiveness, springiness, chewiness, and shear force of the -80 °C group were significantly higher than those of the -20 °C, -35 °C, and -40 °C groups ( P < 0.05). In summary, the -80 °C group demonstrated the closest resemblance to the control group in terms of both body color and muscle quality parameters. These findings provided a theoretical basis for optimizing freezing temperature selection in large yellow croaker preservation.