酸鱼产品中微生物群落结构与品质之间的关系研究

为了解不同酸鱼产品中微生物群落对产品品质的影响。分析不同酸鱼产品中pH、乳酸、游离氨基酸、生物胺,并采用16S rDNA基因测序获得微生物多样性信息,利用固相微萃取和气质联用法(GC-MS)分析挥发性风味物质。考查不同酸鱼产品中微生物多样性与各指标之间的相关性。结果表明:8种市售酸鱼产品生物胺含量较低。酸鱼中存在6种必需氨基酸,2号对滋味具有贡献的氨基酸种类最多。7种酸鱼中均检测到鲜味氨基酸,其中4,6号样品中鲜味氨基酸对滋味的贡献程度较大。GC-MS分析表明醇类、醛类及烃类是酸鱼中主要风味贡献物质,3-甲基-1-丁醇、庚醛、γ-松油烯是酸鱼中共性关键性风味物质。酸鱼优势细菌门为厚壁菌门,优势菌属为乳酸杆菌属、四链球菌属。冗余分析表明增加酸鱼中乳酸杆菌有助于鲜味谷氨酸和天冬氨酸的释放。葡萄球菌、魏斯式菌有利于促进酸鱼中醛类物质的释放,庚醛其清甜味。酸鱼中四联球菌丰度增加有利于3-甲基-1-丁醇和γ-松油烯关键性风味物质的释放,赋予了独特的芳香气味和松油香味。

Relationship between Microbial Community Structure and Quality of Suanyu Products

To understand the effects of microbial communities on product quality of different Suanyu products,pH,lactic acid,free amino acids,biogenic amines in different Suanyu products and microbial diversity information were analyzed by 16S rDNA genes sequencing,and volatile flavors were analyzed by solid phase microextraction and GC-MS. The correlation between microbial diversity and various indicators of different Suanyu products was examined. The results showed that the eight commercially available Suanyu products had lower levels of biogenic amines. There were six essential amino acids in Suanyu products,and the sample 2 had the most amino acid species contributing to the taste. The umami amino acids were detected in all seven kinds of Suanyu products,and the umami amino acids in samples 4 and 6 contributed a lot to the taste. GC-MS analysis showed that alcohols,aldehydes and hydrocarbons were the main flavor contributors in Suanyu products,and 3-methyl-1-butanol,heptanal and γ-terpinene were the key flavors substance in Suanyu products. The dominant bacteria door in Suanyu products was the Firmicutes,and the dominant genus was Lactobacillus and Streptococcus. RDA showed that increasing Lactobacillus in the Suanyu products contributed to the release of glutamic acid and aspartate. Staphylococcus and Weissella were beneficial to promote the release of aldehydes from Suanyu products,and the sweetness of heptanal. The increase in the abundance of Tetragenococcus in Suanyu products was beneficial to the release of key flavor substances of 3-methyl-1-butanol and γ-terpinene,giving a unique aromatic odor and pine oil aroma.