Physicochemical properties, flavor profile, and alleviation of DSS-induced colitis in mice of co-fermented oat beverage.

Oat beverages fermented with lactic acid bacteria represent a promising strategy to improve sensory and nutritional properties. This study presents a systematic investigation into the cooperative fermentation of oats using Lactiplantibacillus plantarum and Streptococcus thermophilus (LP7-ST3) for developing a novel beverage. Compared to single-strain fermentation, LP7-ST3 co-fermentation significantly enhanced the sensory quality and markedly increased the contents of β-glucan, polyphenols, flavonoids, and proteins, resulting in superior antioxidant capacity. Non-targeted metabolomics and flavoromics analyses revealed that co-fermentation profoundly reshaped the volatile and non-volatile metabolite profiles, enriching key flavor compounds and critical metabolic pathways, particularly amino acid biosynthesis. Furthermore, the fermented beverage alleviated disease symptoms, suppressed pro-inflammatory cytokines, and modulated gut microbiota homeostasis by promoting the growth of beneficial bacteria including Muribaculaceae and Dubosiella in a murine model of DSS-induced acute colitis. These findings demonstrate that LP7-ST3 co-fermentation is a powerful strategy for developing high-value oat products with enhanced quality, nutrition, and potential gut health benefits.