温度与干露时间对青蛤品质及营养成分的影响OA

To clarify the effects of temperature and air-exposure duration on the survival,quality traits,and nutritional components of the economically valuable bivalve Cyclina sinensis,we systematically investigated the dynamic changes of key physiological and biochemical indices during 96 h of air-exposure under 4℃and 20℃.Two-year-old adult C.sinensis[shell length:(28.6±1.5)mm,wet weight:(8.6±0.5)g]were acclimated for 7 days before the experiment,with 600 individuals randomly assigned to two temperature groups(3 replicates per group).Mortality,dehydration rate,meat yield,gonadosomatic index(GSI),hepatosomatic index(HSI),and nutritional components(glycogen,crude fat,crude protein,and amino acids)were measured.The results revealed a temperature-dependent survival pattern and physiological response.After 96 h of air-exposure,the mortality rate(3.43%)and dehydration rate(15.6%)of the 4℃group were significantly lower than those of the 20℃group(23.81%and 24.36%,respectively;P<0.05),with the dehydration rate of the 20℃group being 56.15%higher than that of the low-temperature group.In terms of morphological quality indices,meat yield in both groups exhibited a characteristic trend of first increasing and then decreasing,peaking at 24-48 h,and the 4℃group maintained a consistently higher meat yield after 24 h.Both GSI and HSI decreased with prolonged air-exposure,but the decline showed distinct temperature specificity:the 20℃group displayed a significant reduction in HSI at 48 h(P<0.01),while the 4℃group exhibited delayed significant decreases in both GSI and HSI until 72 h.Glycogen was identified as the preferentially catabolized energy reserve.The adductor muscle glycogen content of the 20℃group decreased significantly at 24 h,and by 96 h,it was markedly lower than that of the 4℃group(P<0.05).Crude fat content in the 20℃group declined significantly at 24 h,whereas the 4℃group showed no significant reduction until 72 h.Similarly,crude protein degradation was accelerated at 20℃,with a significant decrease at 48 h,compared to 72 h in the 4℃group,indicating a sequential energy utilization strategy.Amino acid profiling detected 17 amino acids,and glutamic acid(Glu),the key umami amino acid,remained consistently higher in the 4℃group throughout the experiment;at 96 h,Glu content in the 20℃group was significantly lower than that in the 4℃group(P<0.05).These findings demonstrate that 4℃low temperature enhances the air-exposure tolerance of C.sinensis by suppressing metabolic rate,mitigating water loss,and retarding the degradation of energy reserves and umami-related amino acids.We conclude that maintaining 4℃and limiting air-exposure to 72 h is an optimal strategy to preserve the survival rate,quality,and nutritional value of C.sinensis during post-harvest logistics.This study provides critical theoretical insights for optimizing the cold chain transportation system and quality control of C.sinensis.