冻藏温度对南极磷虾品质变化的影响

Effects of Temperature on the Quality of Antarctic Krill(Euphausia superba) during Frozen Storage

本文以感官评分、持水力(WHC)、盐溶性蛋白质含量(SSP)、硫代巴比妥酸反应物(TBARS)为指标,研究了(-20、-30、-40、-50±1)℃四个冻藏温度对南极磷虾品质变化的影响。结果表明,冻藏温度对南极磷虾的品质变化影响差异显著(P<0.05),冻藏温度越高,时间越长,南极磷虾的感官品质和肌肉持水能力越差,蛋白变性和脂肪氧化程度越高。冻藏过程中南极磷虾品质变化趋势基本一致,在-20、-30、-40、-50℃下冻藏180 d后,WHC分别下降了18.27%、15.00%、16.04%、12.92%,SSP分别下降了32.66%、33.99%、24.95%、21.84%,TBARS分别上升了76.38%、78.09%、65.71%、53.55%。-20℃冻藏南极磷虾品质变化较快,在200 d时感官品质难以接受,-30℃冻藏200 d时,感官品质尚可接受,-40℃和-50℃冻藏南极磷虾品质较好,冻藏温度越低越有利于南极磷虾品质的保持。因此,南极磷虾需长期贮藏建议冻藏温度在-30℃及以下。

Antarctic krill was stored at -20, -30, -40, -50±1℃ and their quality was studied based on the indicators of sensory score, water-holding capacity （WHC）, salt soluble protein （SSP）, thiobarbituric acid-reactive substance （TBARS）. Significant differences （P〈0.05） in the quality changes of Antarctic krill were observed during frozen storage at different temperatures. The results showed that the higher the frozen tempemttwe, the worse the sensory quality and the water-holding capacity of Antarctic krill. Severe protein denaturation and fat oxidation were observed with prolonging frozen time. The trend of Antarctic krill deterioration basically kept constant in the process of freezing storage. When stored at -20, -30, -40, -50 ℃ after 180 d, WHC and SSP of Antarctic krill decreased by 18.27%, 15.00%, 16.04%, 12.92% and 32.66%, 33.99%, 24.95%, 21.84%, but TBARS increased by 76.38%, 78.09%, 65.71%, 53.55%, respectively. Sensory quality deteriorated the fastest when stored at -20 ℃ for 200 d, yet it was acceptable when stored at -30 ℃ after 200 d. The sensory quality was much better when stored at -40 ℃ and -50℃. It showed that the lower the frozen storage temperature, the slower the deterioration rate of Antarctic krill. In consequence, the storage temperature below -30℃ was recommended for the storage of Antarctic krill.