Analysis of antioxidant capacity and wine quality characteristics of fermented colored highland barley based on metabolomics

Colored highland barley is a promising nutrient-rich functional food. However, antioxidant capacity after fermentation and the quality of the resulting wine remain unexplored. This study investigated how the accumulation of non-volatile metabolites in four fermented colored highland barley varieties influences antioxidant capacity and wine quality. Comprehensive metabolomic analysis identified 1602 distinct non-volatile metabolites, with 486, 229, and 392 showing differential accumulation in black, purple, and blue varieties, respectively, compared with the yellow variety. Key differentially accumulated metabolites were enriched in flavonoid, flavone, flavonol, and anthocyanin biosynthesis pathways, significantly influencing antioxidant capacity. Interactions among glucose, organic acids, and metabolites contributed to the unique flavor of highland barley wine. Differences in physicochemical characteristics and flavor compounds offer consumers a diverse selection of highland barley wines. These results provide valuable insights for the further investigation of functional components in colored highland barley and the development of high-quality highland barley wine.