Isoflavone aglycones enrichment in soybean sourdough bread fermented by lactic acid bacteria strains isolated from traditional Qu starters: Effects on in vitro gastrointestinal digestion, nutritional, and baking properties

Background and objectives In this study, 165 lactic acid bacteria (LAB) strains were isolated from three traditional Qu (LQ, XQ, and DQ) starters and screened for isoflavone glycoside biotransformation ability. The selected and identified strains were used as starter culture to enrich isoflavone aglycone in soybean sourdough bread (SSB). The in vitro gastrointestinal digestion, nutritional, and baking quality of soybean sourdough bread were determined. Findings Based on yield, three strains identified as Pediococcus pentosaceus (D14, X11; 0.4940 and 0.5243 mg/g, respectively) and Lactobacillus plantarum group (L1, 0.6113 mg/g) showed the highest (p