盐地碱蓬发酵动力学模型构建及抗氧化功能评价

对盐地碱蓬发酵过程中不同发酵时间的酵母菌、乙醇、还原糖、pH值、可滴定酸、总酚等代谢产物及羟自由基清除率、超氧阴离子自由基清除率、还原力等抗氧化指标进行跟踪检测,研究其发酵动力学和抗氧化能力。采用SGompertz、DoseResp、Logistic和Boltzmann模型建立盐地碱蓬发酵动力学模型;利用相关性与主成分分析法构建盐地碱蓬发酵的综合评价指标体系。结果表明,用DoseResp和Boltzmann方程建立酵母菌生长动力学模型,用SGompertz方程建立乙醇产量生成动力学模型,用Logistic方程建立还原糖基质消耗动力学模型,拟合系数R2分别为0.977、0.995、0.982,均呈良好拟合效果;相关性分析结果表明,总酚和有机酸是盐地碱蓬发酵液中抗氧化能力主要来源;主成分分析表明,综合评价指标呈先升高趋于稳定再下降的趋势,综合考虑发酵终点为第8天。该研究揭示了盐地碱蓬发酵过程中代谢产物以及抗氧化活性的变化规律,为盐地碱蓬发酵液的精准制备提供理论基础。

Fermentation Kinetic Modeling and Antioxidant Evaluation of Suaeda salsa

The changes of yeast count, ethanol, reducing sugar, pH, titratable acidity and total phenols as well as antioxidant properties such as hydroxyl and superoxide anion radical scavenging activities and reducing power during Suaeda salsa fermentation by yeast were studied. The SGompertz, DoseResp, Logistic and Boltzmann models were used to investigate the fermentation kinetics. Meanwhile, a comprehensive evaluation index (CEI) system of S. salsa fermentation was developed by correlation analysis (CA) and principal component analysis (PCA). The growth kinetic model of yeast was established using the DoseResp and Boltzmann equations, the kinetic model of ethanol production was established using the SGompertz equation, and the kinetic model of reducing sugar consumption was established using the Logistic equation. The fitting coefficients (R2) of these models were 0.977, 0.995 and 0.982, respectively, indicating excellent goodness of fit. CA showed that total phenols and organic acid were the major contributors to the antioxidant capacity of fermented S. salsa. PCA showed that the CEI value increased first, then leveled off, and finally decreased. The fermentation endpoint was on the eighth day in overall consideration. The results of this study provide a theoretical basis for the precision preparation of fermented S. salsa.