[论文解读] Electro-stimulation of Saccharomyces cerevisiae wine yeasts by Pulsed Electric Field and its effect on fermentation performance

Jessy Mattar, Mohammad Turk+4 more|arXiv (Cornell University)|Apr 21, 2013

Microbial Inactivation Methods参考文献 40被引用 4

一句话总结

本研究调查了脉冲电场（PEF）预处理酿酒酵母（*Saccharomyces cerevisiae*，Actiflore F33）对提升葡萄酒发酵性能的影响。在100 V/cm和6000 V/cm电场强度下进行PEF处理，显著加快了滞留期的糖分消耗，40小时后6000 V/cm处理组的果糖消耗量比对照组高出3.98倍，120小时时质量损失减少30%，即在120小时内达到对照组需140小时才能实现的发酵程度。

ABSTRACT

The batch fermentation process, inoculated by pulsed electric field (PEF) treated wine yeasts (S. cerevisiae Actiflore F33), was studied. PEF treatment was applied to the aqueous yeast suspensions (0.12 % wt.) at the electric field strengths of E=100 and 6000 V/cm using the same pulse protocol (number of pulses of n=1000, pulse duration of ti=100 mks, and pulse repetition time of dt=100 ms). Electro-stimulation was confirmed by the observed growth of electrical conductivity of suspensions. The fermentation was running at 30°C for 150 hours in an incubator with synchronic agitation. The obtained results clearly evidence the positive impact of PEF treatment on the batch fermentation process. Electro-stimulation resulted in improvement of such process characteristics as mass losses, consumption of soluble matter content (°Brix) and synthesis of proteins. It also resulted in a noticeable acceleration of consumption of sugars at the initial stage of fermentation in the lag phase. At the end of the lag phase (t=40 hours), consumption of fructose in samples with electrically activated inocula exceeded fructose consumption in samples with control inocula by 2.33 times when it was activated at E=100 V/cm and by 3.98 times after treatment at E=6000 V/cm. At the end of the log phase (120 hours of fermentation), 30% mass reduction was reached in samples with PEF-treated inocula (E=6000 V/cm), whereas the same mass reduction of the control sample required approximately, 20 hours of extra fermentation. The possible mechanisms of electro-stimulation are also discussed in details.

研究动机与目标

• 评估脉冲电场（PEF）预处理对酿酒酵母在葡萄酒生产中发酵性能的影响。
• 确定通过PEF进行电刺激是否能增强发酵滞留期和对数生长期的代谢活性。
• 量化发酵动力学的改善情况，包括糖分消耗、质量损失和蛋白质合成。
• 确定最优PEF参数（1000次脉冲、100 µs脉冲宽度、100 ms重复时间）以最大化发酵效率。
• 探索电刺激在酵母细胞中作用的潜在细胞与代谢机制。

提出的方法

• 对0.12%（wt.）的酿酒酵母悬浮液进行PEF预处理，电场强度分别为100 V/cm和6000 V/cm。
• 采用相同的脉冲参数：1000次脉冲、100 µs脉冲宽度、100 ms脉冲重复时间。
• 通过监测电导率以确认PEF处理对酵母悬浮液的电刺激效应。
• 在30°C下进行批次发酵，持续搅拌150小时，以评估发酵动力学。
• 随时间测量关键发酵参数：质量损失、°Brix降低、果糖消耗及蛋白质合成。
• 将PEF处理的接种物与未处理的对照组进行比较，以评估性能差异。

实验结果

研究问题

• RQ1 PEF预处理酿酒酵母是否能显著加速葡萄酒发酵初期滞留期的糖分消耗？
• RQ2 与对照组相比，PEF处理在发酵过程中对质量损失和可溶性固体（°Brix）降低的促进作用有多大？
• RQ3 PEF处理对酿酒酵母在批次发酵期间的蛋白质合成和代谢活性有何影响？
• RQ4 PEF电场强度（100 V/cm与6000 V/cm）与发酵性能提升之间存在何种关系？
• RQ5 酵母细胞中观察到的电刺激效应的潜在细胞机制是什么？

主要发现

• 在6000 V/cm电场强度下PEF预处理后，40小时发酵时果糖消耗量比对照组高出3.98倍。
• 在40小时时，6000 V/cm处理组的果糖消耗量是100 V/cm处理组的2.33倍。
• 至120小时，PEF处理组（6000 V/cm）的质量损失达到30%，而对照组需额外20小时才能达到相同水平。
• 通过PEF处理后酵母悬浮液电导率的可测量增加，证实了电刺激效应。
• PEF处理提升了整体发酵性能，包括更快的可溶性物质消耗和更优的蛋白质合成。
• 本研究表明，PEF预处理能显著加速发酵初期，特别是在滞留期，且不改变核心发酵工艺。