传统鲊鱼固态发酵过程中细菌群落与挥发性风味物质的相关性

The potential correlation between bacterial community and the characteristic volatile flavour of traditional fermented fish during solid fermentation

目的:了解传统鲊鱼发酵过程中微生物演替及挥发性风味物质的变化规律。方法:采用传统微生物计数、高通量测序、气相色谱—质谱联用等方法,探究传统鲊鱼固态发酵过程中(0~180 d)微生物菌消长和挥发性风味化合物的变化以及两者的相关性。结果:传统微生物计数和高通量测序两种方法得出葡萄球菌、乳酸菌类是传统发酵鲊鱼发酵过程中的主要优势细菌属。在发酵0~180 d的样品中共检出挥发性化合物69种,主要包括酸类、醇类、醛类、酮类、含N化合物、含苯化合物、芳香烷烃化合物、酯类,其种类和含量随着发酵时间变化而变化。相关性分析发现,葡萄球菌与含N化合物类呈正相关,与醇类化合物负相关;乳酸菌与壬酸、1-辛烯-3-醇、壬醛、肉豆蔻醛、2,4-二甲基苯乙烯、癸烯、己酸乙酯显著正相关(0.01<P<0.05),与庚酸、3-甲基丁酸、2,3-丁二醇、2,6-二叔丁基对甲酚、胡椒烯、肉豆蔻乙酯显著负相关;柠檬酸杆菌、特布尔氏菌属、嗜冷杆菌属、不动杆菌属、海洋螺菌目、黄杆菌目等微生物虽然在整个发酵过程中相对丰度不高,但与风味物质形成也存在明显的相关性。结论:微生物群落与挥发性风味化合物随发酵时间的延长发生一系列的变化,两者之间具有显著相关性。

Objective:This study aimed to investigate the microbial succession and the changes of volatile flavor substances in traditional fermented fish.Methods:Traditional microbial counting methods,high-throughput sequencing,gas chromatography-mass spectrometry(GC-MS)were applied to explore the effects of different fermentation times of traditional fermented fish(0~180 d)on microflora changes and the volatile flavor compounds during the processing of the solid fermentation process of traditional fermented fish as well as on the correlation between them.Results:The results showed that the main dominant bacterial genera included Staphylococcus,Lactobacillus,etc.That there were 69 volatile flavor components in fermentation process,mainly including acids,alcohols,aldehydes,ketones,N compound;benzene compound,alkyl aromatic compound,esters.and their types and contents changed with the fermentation time.The correlation analysis results showed that Staphylococcus was positively correlated with N-containing compounds and negatively correlated with alcohols.Lactobacillus was significant positively correlated with nonanoic acid,1-octen-3-ol,nonanal,tetradecanal,2,4-dimethyl styrene,decyl ene,ethyl caproate(0.01<P<0.05).And negatively correlated with heptenic acid,3-methylbutyric acid,2,3-butanediol,2,6-di-tert-butyl p-cresol,Copaene and myristic ethyl ester.Although the relative abundance of microorganisms such as Citrobacter,Turbulella,Psychrobacter,Acinetobacter,Oceanospirillales and Flavobacteria was relatively low in the whole fermentation process,there was also an obvious correlation with the formation of flavor substances.Conclusion:The microbial community and volatile flavor compounds have a series of changes with fermentation time,and there is a significant correlation between them.