南瓜醋的澄清工艺优化及其抗氧化活性研究

以南瓜为原料，采用酿酒酵母（Saccharomyces cerevisiae）、巴氏醋杆菌（Acetobacter pasteurianus）沪酿1.01与嗜酸乳杆菌（Lactobacillus acidophilus）复合菌株（接种比例=1∶2∶2）发酵制备新型南瓜醋，采用单因素试验及正交试验优化澄清工艺，分析检测南瓜浆及南瓜醋中有机酸，并考察南瓜醋的抗氧化能力。结果表明，最佳澄清条件为壳聚糖和明胶体积比1∶5，静置温度25 ℃，静置时间4 h。在此优化条件下，南瓜醋透光率可达（93.1±1.2）%。南瓜果醋中有机酸种类丰富，其中乙酸和乳酸分别为3.0 g/L和0.49 g/L，总抗氧化能力和羟基自由基清除能力分别可达1.3 U/mL、71%，表现出了良好的体外抗氧化活性。

Clarification technology optimization and antioxidant activity analysis of pumpkin vinegar

Using pumpkin as raw material, a new pumpkin vinegar was prepared by fermentation with compound-strain of Saccharomyces cerevisiae, Acetobacter pasteurianus Huniang 1.01 and Lactobacillus acidophilus (inoculation ratio=1∶2∶2). Using single factor and orthogonal experiments to optimize the clarification technology, the organic acids in pumpkin pulp and pumpkin vinegar was analyzed and determined, and the antioxidant activity of the pumpkin vinegar was investigated. Results showed that the optimal clarification condition was chitosan to gelatin ratio 1:5, standing temperature 25 ℃, and standing time 4 h. Under the optimal condition, the transmittance of the pumpkin vinegar was (93.1±1.2)%. The types of organic acids in pumpkin vinegar were abundant, and the contents of acetic acid and lactic acid were 3.0 g/L and 0.49 g/L, respectively. The total antioxidant capacity and hydroxyl radical scavenging capacity of pumpkin vinegar was 1.3 U/ml and 71%, respectively, which showed good in vitro antioxidant activity.