辐照对小龙虾常温贮藏品质的影响

Effect of Irradiation on Storage Quality of Crayfish at Room Temperature

为研究常温贮藏条件下辐照对熟制小龙虾品质变化规律的影响,采用60Co-γ射线对真空包装条件下的熟制小龙虾进行辐照灭菌处理,并设置2.93、6.62、8.50、10.66 kGy 4个辐照剂量组,将未辐照组作为对照组,通过测定菌落总数、总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、蛋白质特性等相关指标研究60Co-γ射线辐照灭菌对小龙虾常温贮藏货架期及蛋白特性的影响。结果表明:不同辐照剂量虾肉贮藏过程中的初始菌落总数存在显著差异,10.66 kGy组贮藏0 d的菌落总数仅为76 CFU/g,比未辐照组贮藏0 d的菌落总数降低90%以上,且辐照组的TVB-N含量增长趋势明显低于未辐照组,这说明辐照剂量越高,灭菌效果越明显;10.66 kGy组小龙虾辐照后肌原纤维蛋白含量为10.07μg/mL,未辐照组为14.48μg/mL,高剂量辐照组的肌原纤维蛋白含量比低剂量辐照组明显降低,说明辐照促进了蛋白质的氧化分解,对其营养成分有一定影响。当辐照剂量为6.62 kGy时,小龙虾货架期得到有效延长的同时也更好维持了虾肉品质。

In order to study the effect of irradiation on the quality of cooked crayfish stored at room temperature,60 Coγ-ray was used to sterilize cooked crayfish with vacuum packaging.Four irradiation dose groups of 2.93,6.62,8.50,10.66 kGy were set up,and non-irradiated samples were used as control.Total viable count,total volatile basic nitrogen(TVB-N)content and protein characteristics were determined to evaluate the effect of 60 Coγ-ray irradiation on the shelf life and protein characteristics of crayfish stored at room temperature.The results showed that there were significant differences in the initial total number of colonies on cooked crayfish subjected to different irradiation doses.On day 0,the total number of colonies in the 10.66 kGy group was only 76 CFU/g,which was 90%less than that in the control group,and the growing trend of TVB-N content in the irradiated group was significantly lower than that in the control group,indicating that the higher the irradiation dose,the more obvious the sterilization effect.The myofibrillar protein content of the 10.66 kGy group was 10.07μg/mL compared to 14.48μg/mL for the control group.The myofibrillar protein content of the high-dose irradiation group was significantly lower than that of the low-dose group,indicating that the irradiation promoted the oxidative decomposition of protein,affecting the nutritional composition of cooked crayfish.The irradiation dose of 6.62 kGy effectively prolonged the shelf life of cooked crayfish and maintained the nutritional quality.