巴氏醋酸杆菌醋酸发酵工艺的优化

Technology optimization of acetic acid fermentation of Acetobacter pasteurium

分析比较了巴氏醋酸杆菌AC2005和恶臭醋酸杆菌AS1.41的菌种性能,发现菌株AC2005对酒精和醋酸的耐受性较AS1.41优越。采用响应面分析方法对巴氏醋酸杆菌AC2005初始发酵培养基进行了优化。确定了其最佳水平组合为酒精浓度2.7%、醋酸浓度2.6g/100mL、装液量40.0mL时,酒精转化率为97.5%,醋酸浓度可达到5.2g/100mL。在此基础上初步建立了巴氏醋酸杆菌AC2005单批补料的发酵工艺,在发酵过程中补加3次山楂果酒以维持发酵液中酒精浓度为2.0%vol～2.5%vol,发酵周期80h～85h,醋酸浓度可达7.0g/100mL～8.0g/100mL。

The performance of Acetobacte pasteurium AC2005 and Acetobacter rancens AS 1.41 were compared. AC2005 showed a better toleration to alcohol and acetic acid than AS1.41. With Response Surface Methodology, the initial fermentation medium of AC2005 was optimized. The optimal medium contained 2.7% alcohol concentration and 2.6 g/100 ml acetic acid, by which the alcoholic conversion rate was 97.5% and the concentration of acetic acid was up to 5.2 g/100 ml when the medium volume was 40.0 mL. Based on this study, the fed-batch fermentation technology ofA. pasteurium AC2005 was established. Hawthorn fruit wine was added to the broth for three times to maintain a 2.0%-2.5% （v/v） alcohol concentration in fermentation. The concentration of acetic acid reached 7.0g/100 ml-8.0g/100 ml when fed-batch fermentation time was 80h-85h.