响应面法优化黄浆水发酵液制备工艺及其抗氧化活性研究

Optimization of Preparation of Fermented Tofu Whey by Response Surface Methodology and Their Antioxidant Activity

采用植物乳杆菌(Lactobacillus plantarum)、嗜酸乳杆菌(Lactobacillus acidophilus)和清酒乳杆菌(Lactobacillus sakei)3种乳酸菌对黄浆水进行组合发酵,以发酵液DPPH自由基清除率为评价指标,研究发酵温度、发酵时间、脱脂乳粉添加量、葡萄糖添加量和接种量对发酵液的影响。在单因素试验基础上,采用响应面法优化制备高抗氧化活性黄浆水发酵液的工艺条件。结果表明最佳发酵参数为:接种量1%、发酵温度37℃、发酵时间37.50 h、脱脂乳粉添加量8%、葡萄糖添加量5%。在此条件下制备的黄浆水发酵液DPPH自由基清除率为82.36%。抗氧化活性试验表明:黄浆水发酵液提取物抗氧化能力得到显著提升,其清除DPPH自由基、羟自由基和ABTS自由基的半抑制质量浓度(IC50)分别为2.03 mg/mL、1.12 mg/mL和0.30 mg/mL。

The purpose of this study was to investigate the optimal fermentation conditions(fermentation temperature,fermentation time,skim milk content,glucose content and inoculum amount)on the DPPH scavenging rate of fermented tofu whey using Lactobacillus plantarum,Lactobacillus acidophilus and Lactobacillus sakei.On the basis of single factor test,the response surface methodology(RSM)was used to optimize the preparation of fermented tofu whey with high antioxidant activity.The results showed that the optimal fermentation conditions were inoculum amount of 1%,fermentation temperature of 37℃,fermentation time of 37.50 h,skimmed milk content of 8%and glucose content of 5%.The DPPH scavenging rate under the optimal conditions was 82.36%.The antioxidant activity test showed that the antioxidant capacity of the fermented tofu whey extracts was significantly improved with half inhibitory concentration(IC50)for scavenging DPPH,hydroxyl and ABTS radicals of 2.03 mg/mL,1.12 mg/mL and 0.30 mg/mL,respectively.