合成菌群的构建及其对发酵香肠风味的改良效果

Construction and Evaluation of Synthetic Microbiota as a Starter Culture for Flavor Improvement in Fermented Sausage

以自然发酵香肠为研究对象,通过分析其细菌群落优势菌属(相对丰度>1%)、共现菌属(Spearman相关性系数|ρ|>0.5,P<0.05),以及与挥发性风味物质显著相关(P<0.05)的菌属,确定出调控自然发酵香肠典型风味的核心菌群,据此构建合成菌群,与进口商业发酵剂发酵香肠进行对比,分析合成菌群对发酵香肠感官和风味的改良效果。结果表明:自然发酵香肠的核心菌属为葡萄球菌属(Staphylococcus)、乳杆菌属(Lactobacillus)、假单胞菌属(Pseudomonas)和链球菌属(Streptococcus),以上述菌属对应的代表性菌种清酒乳杆菌(Lactobacillus sakei)、嗜热链球菌(Streptococcus thermophilus)、马胃葡萄球菌(Staphylococcus equorum)和木糖葡萄球菌(Staphylococcus xylosus)构建的合成菌群制备改良发酵香肠,其感官特性及风味明显优于商业发酵剂制备发酵香肠,具体表现为:前者的清新味和甜香味较为明显,酸味、咸味和金属异味较淡,特别是具有潜在清新味和果香味的醛类和芳香烃类物质含量显著高于后者(P<0.05)。

By analyzing the dominant bacterial genera(relative abundance>1%),co-occurring genera(Spearman correlation coefficient|ρ|>0.5,P<0.05)and flavor-producing ability of genera in spontaneously fermented sausage,the core bacterial community responsible for regulating the typical flavor of fermented sausage were identified.Based on this,a synthetic microbiota was constructed and evaluated for its efficacy in improving the sensory and flavor profile of fermented sausage using imported commercial starters as the control.The results showed that the core bacterial genera of spontaneously fermented sausage were Staphylococcus,Lactobacillus,Pseudomonas and Streptococcus.The synthetic microbiota consisting of Lactobacillus sakei,Streptococcus thermophilus,Staphylococcus equorum and Staphylococcus xylosus as representative species of these genera were more effective in improving the sensory characteristics and flavor of fermented sausage than the commercial starter cultures.Specifically,the former had a clean and sweet aroma as well as light sour and salty taste and metallic odor,and contained significantly higher contents of aldehydes and aromatic hydrocarbons than the latter(P<0.05).