Microbial Oxidative Stress in Food Fermentations: A Comprehensive Review

This review provides a comprehensive analysis of microbial oxidative stress in food fermentations, establishing it as a central factor that governs microbial physiology, process efficiency, and final product quality. We systematically dissect the dual nature of oxidative stress by first detailing its endogenous sources and exogenous drivers. The review then explores its dichotomous impact, contrasting the role of low‐level reactive oxygen species (ROS) as essential signaling molecules that trigger adaptive defenses, with the detrimental effects of excessive ROS accumulation that causes widespread macromolecular damage and inhibits fermentation. We summarize the sophisticated sensing and regulatory networks in bacteria and fungi that orchestrate multilayered defenses, including enzymatic scavenging, redox buffering, and damage repair systems. A key insight is that oxidative stress can be viewed as a process‐dependent redox variable that may be monitored and modulated to improve fermentation robustness and product quality. In conclusion, oxidative stress represents a redox dimension with strong potential for process management, but its practical use requires process‐specific validation linking redox indicators with fermentation performance and product quality. Integrating validated strain improvement strategies with process‐specific control may help mitigate cellular damage while preserving beneficial stress responses, thereby supporting more robust, efficient, and high‐quality food fermentations.