复合乳酸菌发酵怀山药工艺及其抗氧化活性

该试验利用单因素试验和响应面试验对复合乳酸菌发酵怀山药的工艺进行了优化，并以羟基自由基、超氧自由基、DPPH自由基清除率和还原力为评价指标，研究发酵液的抗氧化活性。 结果表明，最佳发酵条件为发酵时间23 h、发酵温度38 ℃、接种量3%，此条件下乳酸含量最高，为1.42%；怀山药酶解发酵液对羟基自由基、超氧自由基、DPPH自由基清除率分别为99.95%、94.45%、89.65%，较发酵前均有不同程度的提高；还原力提高了0.085。

Optimization of fermentation process of Chinese yam by compound lactic acid bacteria and its antioxidant activity

The fermentation process of Chinese yam by compound lactic acid bacteria was optimized by single factor experiments and response surface experiments. Using the scavenging rate of hydroxyl radical, superoxide radical, DPPH free radical and the reducing power as the evaluation indexes, the antioxidant activity of fermentation broth was researched. The results showed that the optimum fermentation conditions were fermentation time 23 h, temperature 38 ℃, inoculum 3%. Under the conditions, lactic acid content was the highest of 1.42%. The scavenging rate of Chinese yam fermentation broth on hydroxyl radical, superoxide radical and DPPH free radical were 99.95%, 94.45% and 89.65%, respectively, which were higher than that of before fermentation. The reducing power increased by 0.085.