Advancements in the Structure, Spatial Configuration, Functional Properties, and Dairy Applications of Lactic Acid Bacteria Exopolysaccharides

Lactic acid bacteria (LAB) have received widespread attention for their ability to metabolize extracellularly to produce polymers with structure-supporting functions. However, a comprehensive understanding of the synthesis of exopolysaccharides (EPS) from LAB to their structure, function, and application areas is still lacking, limiting the development of their value. In this paper, the EPS-producing Lactobacillus species, EPS extraction, isolation and purification, structural identification and chain conformation characterization, functional activities, current status of their application in the dairy industry and current problems are comprehensively reviewed. The progress of EPS structure characterization was mainly focused on chain conformation, whereas little interest was on the relationship between conformation and functional properties. Besides, EPS has variously biological functions, like promoting the proliferation of probiotic bacteria, etc. And the EPS presented fine potentiality to be stabilizers and thickeners for Lactobacillus fermented milk products. Notably, the EPS production ability of LAB is still relatively low, and it is necessary to pay attention to the research on the relationship between yield improvement strategies and structural effects, to provide the scientific and theoretical basis for promoting its application in the food industry.