蓝莓-酸樱桃复合果醋的醋酸发酵工艺优化及抗氧化性研究

以蓝莓和酸樱桃为原料，制备蓝莓-酸樱桃复合果醋。以总酸、感官评分和花青素含量为评定指标，考察沪酿1.01（巴氏醋杆菌）（Acetobacter pasteurianus）接种量、酒精度、发酵温度和发酵时间对复合果醋品质的影响，并在单因素试验的基础上进行响应面试验，确定蓝莓-酸樱桃复合果醋醋酸发酵工艺，并对蓝莓-酸樱桃复合果醋的品质指标与抗氧化性进行评价。结果表明，最佳醋酸发酵工艺参数为：醋酸菌接种量10%，酒精度9%vol，发酵温度30 ℃，发酵时间8 d。在此优化条件下，复合果醋的总酸含量可达（5.01±0.17）g/100 mL，花青素含量为（102.26±0.89） mg/100 mL，感官评分为（87.00±0.42）分。抗氧化实验结果表明，最大DPPH自由基清除率可达（94.1±0.22）%，还原力（OD700 nm值）为（2.21±0.27），表明其抗氧化性较好。

Optimization of acetic fermentation process and antioxidant activity of blueberry and sour cherry compound fruit vinegar

Using blueberry and sour cherry as raw material, the blueberry and sour cherry compound fruit vinegar was prepared. Taking the total acid, sensory scores and anthocyanins contents as evaluation index, the effects of Huniang 1.01 (Acetobacter pasteurianus) inoculum, alcohol content, fermentation temperature and time on the quality of compound fruit vinegar were investigated. On the basis of single factor test, response surface tests were carried out to determine the acetic fermentation process of blueberry-sour cherry compound fruit vinegar, and the quality index and antioxidant capacity of the vinegar were evaluated. The results showed that the optimal acetic fermentation process conditions were as follows: A. pasteurianus inoculum 10%, alcohol content 9%vol, fermentation temperature 30 ℃ and time 8 d. Under the optimal conditions, the total acid content of the compound fruit vinegar could reach (5.01±0.17) g/100 ml, anthocyanin content was (102.26±0.89) mg/100 ml and the sensory score was (87.00±0.42) points. The results of antioxidant experiment showed that the maximum DPPH radical scavenging rate could reach (94.1±0.22) %, the reducing power was (2.21±0.27) (OD700 nm value), indicating the antioxidant activity of the compound fruit vinegar was good.