Study on Physicochemical Properties, Antioxidant Activity and Flavor Quality in the Fermentation of a Plant-Based Beverage by Different Lactic Acid Bacteria.

This study investigated the effects of three different lactic acid bacteria (LAB) strains (Limosilactobacillus fermentum 14, Limosilactobacillus reuteri 18, and Lactiplantibacillus plantarum CAU808) on the nutrient components, bioactivity, and flavor profiles of a medicinal and edible homologous (MEH) plant-based beverage (QJ). Results demonstrated that QJ served as an excellent substrate for LAB growth, with viable counts of all three LAB exceeding 8.5 log CFU/mL after fermentation. Fermentation significantly reduced soluble sugar contents while increasing organic acids levels. A slight enhancement in ABTS radical scavenging capacity was also observed. Electronic tongue (E-tongue) analysis revealed that LAB fermentation markedly decreased bitterness and enhanced sourness, sweetness, and umami, thereby improving the overall taste profile. Furthermore, electronic nose (E-nose) and HS-SPME-GC-MS analyses indicated distinct alterations in odor characteristics post-fermentation. A total of 87 volatile compounds were identified, with alcohols constituting the predominant group. Compared to the other two strains, Lactiplantibacillus plantarum CAU808 demonstrated superior fermentation performance and more favorable flavor characteristics. These findings provide a theoretical basis for utilizing LAB fermentation to optimize the flavor of MEH plant-based beverages.