Optimization of fermentation process of lotus root vinegar prepared with lotus root pomace by response surface methodology

To optimize the fermentation conditions of lotus root pomace vinegar by response surface analysis ( RSM) . Based on the results of single factor experiment of three factors, the initial alcohol content, the added amount of acetobacter and the time of fermentation, the Box-Behnken experiment was used to optimize the fermentation conditions of lotus root pomace vinegar by response surface analysis. The results showed that the optimum fermentation conditions were as follows: the initial alcohol content was 8.8%, the inoculation amount was 7.3% and the fermentation time was 6 days at the fermentation temperature was30 ℃.Under this condition, the acetic acid yield of lotus root pomace vinegar was 56.3 g/L, which was close to the theoretical predicted value of 56.4279 g/L. The process of the lotus root pomace vinegar was bright orange, acetic acid content was moderate, vitamin C content was higher, heavy metal and microbial indicators were qualified.