Enhanced Quality and Metabolic Profile of Fermented Milk Through Fucose Supplementation with Lactobacillus helveticus

Fermented milk represents an excellent carrier for probiotics, and the incorporation of different carbon sources during fermentation can profoundly affect microbial metabolism. Based on our previous finding that Lactobacillus helveticus DYNDL_20-5 produces fucose-containing exopolysaccharides (EPS), we hypothesized that fucose supplementation could further enhance its metabolic activity and improve fermented milk quality. Thus, this study systematically investigated the impact of culturing L. helveticus DYNDL_20-5 with fucose (CMF5) on the quality characteristics and metabolic profiles of fermented milk. Compared to the control group without fucose and L. helveticus (CM), the CMF5 group demonstrated that L. helveticus effectively utilized fucose to promote acid production, enhance the fermentation process, increase microbial abundance, and enrich beneficial genera. Furthermore, the CMF5 group exhibited significantly improved textural properties, including enhanced viscosity and gel strength. Metabolomic analysis revealed that the addition of fucose and L. helveticus significantly influenced the metabolism of organic acids, fatty acids, and amino acids during milk fermentation, leading to increased concentrations of various metabolites associated with sensory quality, nutritional value, and health-promoting benefits. The findings of this study provide valuable insights into the synergistic effects of L. helveticus DYNDL_20-5 and fucose on fermented milk quality, offering a theoretical foundation for the development of novel functional dairy products with enhanced nutritional and sensory attributes.