60Coγ-射线及电子束辐照对冷鲜鸡菌群多样性的影响

为探明γ-射线与电子束辐照对冷鲜鸡微生物含量和微生物群落多样性的影响,采用2.5 kGy剂量的γ-射线和电子束辐照处理真空包装冷鲜鸡,对其贮藏期内菌落总数、群落结构进行测定分析。结果表明,两种射线均能显著(P<0.05)降低冷鲜鸡菌落总数;高通量测序后得到了9门,62属的菌群结构,在门水平上,变形菌门(Proteobacteria)、厚壁菌门(Firmicutes)、梭杆菌门(Fusobacteria)、拟杆菌门(Bacteroidetes)为优势菌群;在属水平上,贮藏0 d时,对照组内环丝菌属(Brochothrix)、希瓦氏菌属(Shewanella)、不动细菌属(Acinetobacter)为优势菌群;贮藏5 d时,对照组内希瓦氏菌属(Shewanella)、γ-射线组内嗜冷菌属(Psychrobacter)、电子束处理组内希瓦氏菌属(Shewanella)为优势菌群;贮藏10 d时,对照组内嗜冷菌属(Psychrobacter)、γ-射线组不动细菌属(Acinetobacter)、电子束处理组内希瓦氏菌属(Shewanella)为优势菌群;贮藏15 d时,对照组内嗜冷菌属(Psychrobacter)、γ-射线组希瓦氏菌属(Shewanella)、电子束处理组内希瓦氏菌属(Shewanella)成为优势菌群。由此可知,γ-射线与电子束辐照均对冷鲜鸡微生物数量和群落结构产生显著(P<0.05)影响。

Effects of 60Co γ-ray and Electron Beam Irradiation on the Bacterial Community Diversity of Cold Fresh Chicken

To investigate the impact of γ-ray and electron beam( EB) irradiation on the microbial content and bacterial community diversity of cold fresh chicken,vacuum packaging cold fresh chicken was treated through 2.5 kGy dose of γ-ray and electron beam irradiation.The results showed that the two kinds of rays could significantly reduce the total bacterial count in cold fresh chicken,and the 16 S rDNA flora analysis showed that there were 9 phylums with 62 kinds of genera in the cold fresh chicken.Proteobacteria,Firmicutes,Fusobacteria and Bacteroidetes were the dominant bacteria at the phylum level.At the genus level,Brochothrix,Shewanella and Acinetobacter were the dominant bacteria during the early stage of storage( 0 d) of control group.When stored 5 d,Shewanella in the control group,Psychrobacter in the γ-ray group,and Shewanella in the EB processing group were the dominant flora. When stored 10 d,Psychrobacter in the control group,Acinetobacter in the γ-ray group,and Shewanella in the EB processing group were the dominant flora. When stored 15 d,Psychrobacter in the control group,Shewanella in γ-ray group,and Shewanella in EB processing group became dominant flora. As a result,both of γ-ray and electron beam irradiation had a significant( P < 0.05) effect on the microbial contents and structure of community of cold fresh chicken.