Supplementary data.docx

The selection of appropriate starter cultures is a crucial factor in determining the quality of fermented soymilk products. This study evaluated the effects of a combined starter culture of <i>Enterococcus faecium </i>CGMCC 29309 and <i>Lactiplantibacillus plantarum</i> CGMCC 29306 on the microbiological, physicochemical, textural and rheological characteristics of fermented soymilk. The results indicated that the mixed-strain fermentation significantly increased the concentrations of free isoflavones, free amino acids, free fatty acids, and aroma compound acetaldehyde, 2,3-butanedione and acetoin, and significantly reduced the level of beany compound hexanal. The fermentation also greatly improved the textural and rheological characteristics of fermented soymilk. The <i>Enterococcus faecium</i> strain played a leading role in the mixed-strain fermentation, whereas the <i>Lactiplantibacillus plantarum</i> strain was found to be necessary due to its greater ability to break down conjugated isoflavones. This study provides a theoretical basis for using the combined lactic acid bacteria starter to prepare premium fermented soymilk products.

适宜发酵剂的筛选是决定发酵豆乳产品品质的关键因素。本研究评估了屎肠球菌（Enterococcus faecium）CGMCC 29309与植物乳杆菌（Lactiplantibacillus plantarum）CGMCC 29306组成的复合发酵剂对发酵豆乳的微生物学、理化、质构及流变学特性的影响。研究结果显示，混合菌株发酵可显著提升游离异黄酮、游离氨基酸、游离脂肪酸以及香气成分乙醛、2,3-丁二酮和乙酰甲基甲醇的含量，同时显著降低豆腥味成分己醛的水平。该发酵方式还可显著改善发酵豆乳的质构与流变学特性。在混合菌株发酵体系中，屎肠球菌菌株发挥主导作用，而植物乳杆菌菌株因具备更强的结合型异黄酮分解能力，亦是不可或缺的组成部分。本研究为利用复合乳酸菌发酵剂制备高品质发酵豆乳产品提供了理论依据。