高浓度柠檬酸对酿酒酵母生长的抑制效应

Inhibiting effects of high concentration of citric acid on the growth of Saccharomyces cerevisiae

在果酒酿造过程中,酿酒酵母会面临果实中有机酸尤其柠檬酸的胁迫。该研究系统地考察了酿酒酵母(Saccharomyces cerevisiae)EC1118和2323在酵母膏蛋白胨葡萄糖液体培养基中的生长情况,在3种不同柠檬酸浓度和pH值培养条件下,分析两种酿酒酵母的生长曲线,揭示柠檬酸对酿酒酵母生长抑制的机制。结果表明,高浓度柠檬酸(0.10～0.40 mol/L)会抑制酿酒酵母生长;pH值≤2.80时,酿酒酵母的生长均受到抑制。高浓度柠檬酸的抑制效应是氢离子和柠檬酸根的叠加影响,而且柠檬酸根的影响占主导。该研究结果将为进一步解除有机酸对酿酒酵母抑制效应以及果酒研制提供一定参考。

In the brewing process of fruit wine, the Saccharomyces cerevisiae endured the stress of organic acid in the fruit, especially the citric acid.The growth condition of S. cerevisiae EC1118 and 2323 was systematically investigated in the liquid medium with yeast peptone dextrose. Their growth curves were analyzed under three culture conditions of citric acid concentration and pH value, the growth curve of S. cerevisiae was analyzed and the inhibiting mechanism of citric acid on S. cerevisiae was revealed. Results demonstrated that high concentration（0.10-0.40 mol/L） citric acid could inhibit the growth of S. cerevisiae. Meanwhile, the growth of S. cerevisiae was inhibited with pH value lower than 2.80. The inhibitory effects of high concentration citric acid were the superimposition effect of hydrogen ion and citrate, and the effect of citrate was dominant. The study would provide some references for further removing the inhibitory effect of organic acids on S. cerevisiae and the development of fruit wine.