Abstract
Steering microbial metabolic stability in fermentation is a recurrent goal in microbial food production. Indigenous liquor fermentation typically relies on complex microbiome metabolism, making it difficult to steer fermentation towards consistent high-quality products. Here, we conducted a three-step experiment to identify instability factors and explore ways to steer fermentation stability in lab-scale settings. We found that the metabolic stability of the microbiome fluctuates due to fermentation parameters, dynamic benefit allocation between yeasts and Lactobacilli, and metabolic network redundancy. In addition to parameters control, short-term metabolic stability requires stable microbial benefit allocation, whereas long-term stability requires proper functional redundancy. Rationally setting initial parameters and the microbial inoculation ratio is a practical way to optimize metabolic stability for stable indigenous liquor fermentation. Our study provides new insights into microbiome metabolism control and shows the feasibility of enhancing fermentation stability through appropriate initial conditions, enabling more controlled and efficient microbial food production systems.