菌种和底物因素对荔枝发酵液主要功效酶活性的影响

Effect of fermentation strains and substrates on effect of main enzyme activity of mixed fermented liquid of litchi

中文关键词:  荔枝  发酵  酵母菌  乳酸菌  酶活性

英文关键词:litchi  fermentation  yeast  lactic acid bacteria  enzyme activity

中文摘要:

      目的 探究酵母和乳酸菌菌种及底物因素对荔枝汁发酵特性的影响。方法 采用不同的酵母、乳酸菌及组合对荔枝汁进行发酵, 测定发酵液中超氧化物岐化酶(SOD酶)、淀粉酶活性及总酚含量; 结合单因素和Box-Benhnken设计试验进行响应面统计分析, 以优化发酵底物参数工艺条件。结果 荔枝汁发酵基质接入葡萄酒酵母与果酒酵母混菌(3:7, V:V), 接种量为4%, 25 ℃下发酵24 h; 以保加利亚乳杆菌和嗜热链球菌菌种(8:2, V:V)混合菌种进行乳酸菌发酵, 接种量为2%, 37 ℃下发酵16 h, 发酵液中SOD酶与淀粉酶活性较高。荔枝汁发酵底物优化的参数为: 初始可溶性固形物含量为20 °Brix, N源添加量为1.0%, pH为3.0, 终发酵液的SOD酶活性可达52.17 U/mL、淀粉酶活性为12.15 U/mL、总酚含量为12.76 mg/100 mL, 与模型预测值相近。结论 荔枝汁通过混菌发酵, 可制备具有一定功效成分的发酵饮料。

英文摘要:

      Objective To study the effect of different fermentation strains and substrates on enzyme activity of mixed fermented liquid of litchi. Methods Litchi pulp was used as material for fermentation with several different yeasts and lactic acid bacteria and their combination. The superoxide dismutase (SOD), amylase activity and total phenolic content during fermentation were determined. Based on the results of single factor and Box-Benhnken experiment, response surface statistical analysis and optimization of fermentation substrate parameters were performed. Results The higher activities of superoxide dismutase (SOD) and amylase in fermented liquid of litchi were obtained under the following conditions: volume ratio of wine yeast mixed with fruit wine yeast species was 3:7, inoculum size was 4%, fermentation time was 24 h at 25 ℃; volume ratio of Lactobacillus bulgaricus mixed with Streptococcus thermophilus strains was 8:2, inoculum size was 2%, fermentation time was 16 h at 37 ℃. The optimal fermentation substrates were as follows: initial soluble solids content was 20 °Brix, N source content was 1.0% and pH was 3.0. The superoxide dismutase (SOD), amylase activity and total phenolic content were 52.17 U/mL, 12.15 U/mL and 12.76 mg /100 mL respectively, which were similar to the models. Conclusion A kind of functional litchi beverage was obtained by mixed fermentation.