INRA, UMR Sciences pour l'oenologie, Montpellier cedex, France.
Int J Food Microbiol. 2011 Oct 17;150(1):42-9. doi: 10.1016/j.ijfoodmicro.2011.07.016. Epub 2011 Jul 27.
Continuous fermentation set-ups are of great interest for studying the physiology of microorganisms. In winemaking conditions, yeasts go through a growth phase and a stationary phase during which more than half of the sugar is fermented. A comprehensive study of wine-yeast physiology must therefore include yeasts in a non-growing phase. This condition is impossible to achieve within a chemostat, which led us to design a multi-stage fermentation device. In this study, we evaluated the ability of such a device to reproduce, in a series of steady states, the conditions of batch fermentation. Two-stage and four-stage fermentations were carried out with two different strains of Saccharomyces cerevisiae. The main characteristics of the fermentation process (biomass growth, by-product content of the medium) were compared with those observed in batch mode at the same stage of fermentation, which was defined by glucose uptake. The four-stage configuration showed a better ability to reproduce batch fermentation characteristics than the two-stage set-up. It also allowed to uncouple the variations of environmental parameters and proved to be a promising tool to gain new insights into yeast metabolism during alcoholic fermentation.
连续发酵装置在研究微生物生理学方面具有重要意义。在酿酒条件下，酵母经历生长阶段和静止阶段，在此期间，超过一半的糖被发酵。因此，对葡萄酒酵母生理学的综合研究必须包括非生长阶段的酵母。在恒化器中，这种条件是不可能实现的，这促使我们设计了一种多阶段发酵装置。在这项研究中，我们评估了该装置在一系列稳定状态下再现分批发酵条件的能力。使用两种不同的酿酒酵母菌株进行了两阶段和四阶段发酵。将发酵过程的主要特征（生物量生长、培养基副产物含量）与在相同发酵阶段（以葡萄糖摄取定义）在分批模式下观察到的特征进行了比较。四阶段配置比两阶段装置更能再现分批发酵的特点。它还可以分离环境参数的变化，并被证明是一种很有前途的工具，可以深入了解酒精发酵过程中酵母的代谢。
