Black rice stepwise fermentation enhances yogurt gel quality: Solidification rate, texture, LAB distribution and viability persistence

Water holding capacity (WHC) and texture stability primarily affect yogurt quality. In this study, black rice stepwise fermented yogurt (FBY) was produced, and the enhancement of texture quality was investigated. Compared with the control, FBY shortened the solidification time by 25.0 %, enhanced WHC and hardness by 13.2 % and 53.8 %, respectively, and increased viscosity. The released dietary fiber and anthocyanidins provided supportive carriers for lactic acid bacteria (LAB), enhancing their distribution and viability. The distributions of starch and fiber in FBY were more detailed. The binding energies of ρ-coumaryl alcohol and cyanidin with β-lactoglobulin showed the lowest levels. Mantel correlation revealed that stepwise fermentation promoted the uniform distribution and viability persistence of LAB, thereby enhancing yogurt solidification, WHC, and texture stability. This study demonstrated the impact of rice stepwise fermentation on yogurt texture, providing an effective strategy for rapid yogurt preparation and long-term stability maintenance.