Microbial fermentation-mediated starch modification: Structural evolution, mechanistic insights, traditional application and future perspectives.

Native starch has intrinsic drawbacks, including retrogradation, syneresis, poor shear stability, weak texture, and low viscosity, which restrict its applications in the food industry worldwide. Fermentation is a mild and sustainable modification method that can reduce retrogradation and syneresis, improve rheological, textural, and thermal properties, and modulate starch digestibility. Unlike previous reviews that mainly summarize fermentation-mediated quality changes, this review integrates predominant microorganisms, fermentation strategies, and traditional food applications, with a core focus on starch functionality. It links alterations in multiscale structure, physicochemical properties, retrogradation behavior, and digestibility to microbial species, substrate sources, and fermentation parameters, thereby exploring the underlying structure-property mechanisms and critically discussing inconsistent findings in the existing literature. Based on genetic engineering and synthetic biology, current challenges and future directions are also discussed, highlighting the potential to shift fermentation from an empirical practice to a controlled, precise technological domain, thereby facilitating the development of functional products with a low glycemic index and longer shelf life.