基于代谢组学的豆乳中乳酸乳球菌乳酸亚种发酵特性分析

Metabolomics Analysis of Fermentation Characteristics of Lactococcus lactis subsp.lactis in Soymilk

目前,国内外关于乳酸乳球菌乳酸亚种的应用研究主要集中于其在牛乳发酵中的特性,而其在豆乳发酵中的应用研究较少。本研究基于发酵指标,采用代谢组学和感官评价对乳酸乳球菌乳酸亚种菌株在豆乳中的发酵特性进行分析。结果表明:具有优良蔗糖代谢特性的DYNDL21-2、DYNDL1-2和FJNDD18M83株乳酸乳球菌乳酸亚种菌株展现出良好的生长和产酸能力;在乳酸乳球菌乳酸亚种发酵豆乳中,菌株DYNDL21-2、FJNDD18M8发酵能明显下调己醛和多种呋喃类杂环化合物的丰度,有效降低豆腥味强度;菌株FJNDD18M8发酵能明显上调乙醛、乙偶姻及2,3-丁二酮等物质丰度,增强发酵豆乳产品的乳香和奶油风味,有效改善豆乳风味。综上,乳酸乳球菌乳酸亚种菌株在豆乳发酵过程中具有优良的发酵特性和较强的代谢能力,但菌株间存在一定的差异。

Most current studies on Lactococcus lactis subsp.lactis are focused on its application in bovine milk,but few studies have been conducted on its application in soymilk.The fermentation characteristics of Lactococcus lactis subsp.lactis in soymilk were analyzed by metabolomics and sensory evaluation in the present study.The results showed that Lactococcus lactis subsp.lactis strains DYNDL21-2,DYNDL1-2 and FJNDD18M8 showed good sucrose metabolism capacity,growth and acid production ability.The abundance of hexanal and various heterocyclic compounds such as furan in fermented soymilk was significantly down-regulated by DYNDL21-2 and FJNDD18M8,which effectively reduced the intensity of beany odor.Fermentation with FJNDD18M8 significantly up-regulated the abundance of acetaldehyde,acetoin and 2,3-butanedione in soymilk,enhancing the milky aroma and creamy flavor and improving the overall flavor.In conclusion,Lactococcus lactis subsp.lactis has excellent fermentation characteristics and strong metabolic capacity during soymilk fermentation,but there are some differences among strains.