Enhancing the Antioxidant Capacity and Quality Attributes of Fermented Goat Milk through Synergistic Action of Limosilactobacillus fermentum WXZ 2-1 with Starter Culture

This study evaluated 75 strains of lactic acid bacteria (LAB) isolated from traditional dairy products in western China for their probiotic properties. Among them, Limosilactobacillus fermentum WXZ 2-1, Lactiplantibacillus plantarum TXZ 2-35, Companilactobacillus crustorum QHS 9, and Companilactobacillus crustorum QHS 10 demonstrated potential probiotic characteristics. The antioxidant capacity of these 4 strains was assessed, revealing that L. fermentum WXZ 2-1 exhibited the highest antioxidant capacity. Furthermore, when cocultured with Streptococcus salivarius ssp. thermophilus and Lactobacillus delbrueckii ssp. bulgaricus, L. fermentum WXZ 2-1 demonstrated a synergistic effect in growth medium and goat milk. To explore its effect on goat milk fermentation, different amounts of L. fermentum WXZ 2-1 were added to goat milk, and its physicochemical properties, antioxidant activity, flavor substances, and metabolomics were analyzed. The study found that the incorporation of L. fermentum WXZ 2-1 in goat milk fermentation significantly improved the texture characteristics, antioxidant capacity, and flavor of fermented goat milk. These findings highlight the potential of L. fermentum WXZ 2-1 as a valuable probiotic strain for enhancing the functionality and desirability of fermented goat milk, contributing to the development of novel functional foods with improved health benefits and enhanced quality attributes.