Optimization of nutrients formula for alcohol vinegar fermentation by response surface methodology

In order to improve the acidity and fermentation efficiency of alcohol vinegar, using the total acid content as the response value, the formula of nutrient salt for alcohol vinegar fermentation was optimized by single factor experiments combined with response surface method. The results showed that MgSO₄, CaCl₂, aspartate (Asp) and proline (Pro) were the main factors affecting the total acid content of alcohol vinegar. The optimal nutrient formula for alcohol vinegar fermentation was as follows: glucose 1.50 g/L, alanine (Ala) 0.15 g/L, Asp 0.44 g/L, Pro 0.18 g/L, ammonium citrate 0.15 g/L, CaCl₂ 0.09 g/L, MgSO₄ 0.09 g/L, pantothenic acid 0.12 g/L. Under these optimal conditions, the total acid content of alcohol vinegar was (53.85±0.22) g/L, which was increased by 12.19% compared with that before optimization.