Grup de Biotecnologia Microbiana dels Aliments, Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, c/Marcel·lí Domingo s/n, 43007 Tarragona, Catalonia, Spain.
Grup de Biotecnologia Enològica, Departament de Bioquímica i Biotecnologia, Facultat d'Enologia, Universitat Rovira i Virgili, c/Marcel·lí Domingo s/n, 43007 Tarragona, Catalonia, Spain.
Int J Food Microbiol. 2023 Nov 2;404:110367. doi: 10.1016/j.ijfoodmicro.2023.110367. Epub 2023 Aug 11.
Progress in oenological biotechnology now makes it possible to control alcoholic (AF) and malolactic (MLF) fermentation processes for the production of wines. Key factors in controlling these processes and enhancing wine quality include the use of selected strains of non-Saccharomyces species, Saccharomyces cerevisiae, and Oenococcus oeni, as well as the method of inoculation (co-inoculation or sequential) and the timing of inoculation. In the present work, we investigated the effects of different inoculation strategies of two Torulaspora delbrueckii (Td-V and Td-P) strains followed by S. cerevisiae. Times (two, four, and six days) and types (co-inoculation and sequential) of inoculation were evaluated on the AF of a synthetic grape must. Furthermore, this synthetic medium was optimized by adding linoleic acid and β-sitosterol to simulate the natural grape must and facilitate reproducible results in potential assays. Subsequently, the wines obtained were inoculated with two strains of Oenococcus oeni to carry out MLF. Parameters after AF were analysed to observe the impact of wine composition on the MLF performance. The results showed that the optimization of the must through the addition of linoleic acid and β-sitosterol significantly enhanced MLF performance. This suggests that these lipids can positively impact the metabolism of O. oeni, leading to improved MLF efficiency. Furthermore, we observed that a 4-day contact period with T. delbrueckii leads to the most efficient MLF process and contributed to the modification of certain AF metabolites, such as the reduction of ethanol and acetic acid, as well as an increase in available nitrogen. The combination of Td-P with Oo-VP41 for 4 or 6 days during MLF showed that it could be the optimal option in terms of efficiency. By evaluating different T. delbrueckii inoculation strategies, optimizing the synthetic medium and studying the effects on wine composition, we aimed to gain insights into the relationship between AF conditions and subsequent MLF performance. Through this study, we aim to provide valuable insights for winemakers and researchers in the field of wine production and will contribute to a better understanding of the complex interactions between these species in the fermentation process.
在酿造生物技术方面的进展使得控制葡萄酒酿造过程中的酒精发酵（AF）和苹果酸-乳酸发酵（MLF）成为可能。控制这些过程和提高葡萄酒质量的关键因素包括使用选定的非酿酒酵母属（非 S. 酵母）、酿酒酵母和酒香酵母属（O. oeni）菌株，以及接种方法（共接种或顺序接种）和接种时间。在本工作中，我们研究了两种毕赤酵母属（Torulaspora delbrueckii）（Td-V 和 Td-P）菌株随后接种酿酒酵母的不同接种策略的影响。评估了不同的接种时间（两天、四天和六天）和类型（共接种和顺序接种）对合成葡萄汁的 AF 的影响。此外，通过添加亚油酸和β-谷甾醇来优化这种合成培养基，以模拟天然葡萄汁并在潜在的测定中获得可重复的结果。随后，用两种酒香酵母属（Oenococcus oeni）菌株对获得的葡萄酒进行 MLF 接种。分析 AF 后的参数以观察葡萄酒成分对 MLF 性能的影响。结果表明，通过添加亚油酸和β-谷甾醇对基质的优化显著提高了 MLF 性能。这表明这些脂质可以积极影响 O. oeni 的代谢，从而提高 MLF 效率。此外，我们观察到与毕赤酵母属接触 4 天可导致最有效的 MLF 过程，并有助于某些 AF 代谢物的修饰，例如减少乙醇和乙酸，以及增加可用氮。在 MLF 过程中，将 Td-P 与 Oo-VP41 共接种 4 天或 6 天的组合显示出在效率方面可能是最佳选择。通过评估不同的毕赤酵母属接种策略、优化合成培养基并研究对葡萄酒成分的影响，我们旨在深入了解 AF 条件与随后的 MLF 性能之间的关系。通过这项研究，我们旨在为葡萄酒酿造领域的酿酒师和研究人员提供有价值的见解，并有助于更好地理解这些物种在发酵过程中的复杂相互作用。
