X射线辐照对冷鲜猪肉品质和货架期的影响

Effects of X-ray Irradiation on Chilled Pork Quality and Shelf Life

为研究X射线辐照对冷鲜猪肉品质的影响。该实验用0.1~1.0 kGy梯度的辐照剂量对纯培养细菌、冷鲜猪肉进行处理,评估不同辐照剂量和贮藏时间下微生物、理化指标和感官特性的变化。结果表明:微生物菌落数随辐照剂量的增加而减少。纯培养大肠杆菌和单核细胞增生李斯特氏菌的D_(10)值分别为0.177 kGy和0.180 kGy。0.6 kGy X射线辐照处理时,纯培养细菌菌落数显著(p<0.05)减少3.0 log值以上;人工接种细菌菌落数显著(p<0.05)减少2.0 log值以上。1.0 kGy辐照处理冷鲜猪肉,固有微生物菌落数显著(p<0.05)减少2.0 log值以上;货架期从原来的4 d延长到9 d;贮藏前期感官评分无显著(p>0.05)差异,后期感官评分下降缓慢;与对照相比TVB-N和pH值的上升速率在贮藏期内显著降低(p<0.05);辐照后冷鲜猪肉TBA值有所增加,但在贮藏中对照组TBA值上升速率大于辐照组。综合考虑,1.0 kGy X射线辐照处理冷鲜猪肉,在保证冷鲜猪肉符合国家食品安全标准规定的同时将货架期延长了4~5 d,为冷鲜猪肉的辐照保鲜技术提供科学依据。

To study the effects of X-ray irradiation on chilled pork quality,irradiation from 0.1 to 1.0 kGy was used to treat cultured pathogens and chilled pork to evaluate changes in microorganism growth,physical and chemical indicators,and sensory characteristics of chilled pork under different irradiation doses and storage times.The number of microbial colonies decreased as the irradiation dose increased.The D_(10) values of cultured Escherichia coli and Listeria monocytogenes were 0.177 kGy and 0.180 kGy,respectively.After treatment by X-ray irradiation at 0.6 kGy,the number of cultured microbial colonies was significantly reduced by more than 3.0 log value(p<0.05),and the number of inoculated microbial colonies decreased significantly by more than 2.0 log value(p<0.05).Furthermore,when chilled pork was treated with 1.0-kGy X-ray irradiation,the number of inherent microbial colonies declined markedly by more than 2.0 log value(p<0.05)while the shelf life was extended from 4 days to 9 days.There was no significant difference in sensory scores(p>0.05)in the early storage period,but in the later period,the sensory score of the irradiated chilled pork slowly decreased.The rates of TVB-N and pH-value increase dropped significantly during the storage period compared with those of the control(p<0.05).The TBA value of the chilled pork increased in all samples after irradiation,but the rate of TBA-value increase in the control group during storage was greater than that in the irradiated group.In summary,1.0-kGy X-ray irradiation treatment of chilled pork meets national food safety standards and extends shelf life by 4~5 days.This finding provides a scientific basis for irradiation-based preservation of chilled pork.