Physicochemical, nutritional, and flavor attributes of Dangshan Su pear fermented with various lactic acid bacteria.

This study evaluated eight lactic acid bacteria (LAB) strains for effects on the physicochemical properties, antioxidant activity, and volatile metabolites of Dangshan Su pear. Two selected strains (Lactiplantibacillus plantarum L3 and Limosilactobacillus fermentum R11) were further characterized for non-volatile metabolite profiles in single and mixed cultures. LAB fermentation significantly enhanced total phenolics and flavonoids, DPPH/ABTS+ scavenging, and α-glucosidase/α-amylase inhibition, with L3 showing the greatest improvement. Aroma remodeling was strain-dependent, with L3 boosting fruity esters and R11 improving mouthfeel. Non-targeted metabolomics revealed extensive remodeling, particularly in the co-culture (L3 + R11). Various metabolites (isoleucine, valine, proline, GABA, choline, and dipeptides) with VIP > 1.0 were significantly increased following fermentation, contributing to flavor formation and nutritional enhancement. Notably, GABA increased by 4.62-fold after R11 fermentation. These results demonstrate that L3 and R11 are effective starter cultures for enhancing pear flavor and nutritional value, offering a feasible strategy for the high-value utilization of pear resources.