Redox balance in wine yeast under hyperosmotic stress and the relation to wine quality

高渗胁迫下葡萄酒酵母的氧化还原平衡及其与葡萄酒品质的关系

• 批准号: 238872-2012
• 负责人: Inglis, Debra
• 金额: $ 1.82万
• 依托单位: Brock University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=570510
• 关键词: Redox; balance; wine; yeast; under

Icewine is the flagship wine of Canada that spearheaded international trade for Canadian wines. It continues to be of critical importance to the Canadian wine industry, with Icewines approved for sale in 2011 worth $100 million. Producing these wines offers many challenges to wine yeast carrying out the fermentations. Solutes in Icewine juice place wine yeast under increased hyperosmotic stress, leading to altered metabolism, fermentation difficulties and ten-times the concentration of acetic acid found in table wines. A high concentration of acetic acid in Icewine is a concern due to its association with wine spoilage. Wine yeast strains display properties that are distinct from well-studied laboratory yeast strains, and these differences can impact on the organoleptic properties of wine. However, the molecular basis of these differences remains largely unknown. The central research goal of this program is to gain a more comprehensive understanding, at the molecular level, of factors influencing wine yeast stress responses during fermentation of concentrated grape juices and how these responses relate to cellular redox balance, glycerol, organic acid production and overall wine quality. We will examine such influences while yeast adapt first to the hyperosmotic stress from concentrated Icewine juice, and then to ethanol and acetic acid stress as fermentation proceeds. Once we understand why certain metabolites are formed during this response, it should be possible to control yeast metabolism to avoid or minimize unwanted compounds such as acetic acid. This research will provide critical information for the development of yeast strains best suited for Icewine and wine styles based on high Brix juice, such as that found in the emerging Canadian appassimento wine style produced from grapes ripened off-vine. This information will be applicable to winemakers, assisting them in maintaining and expanding Canada's global dominance in Icewine quality and supporting their needs as they branch into new wine styles involving high sugar juices.

Icewine是加拿大的旗舰葡萄酒，率先为加拿大葡萄酒进行国际贸易。 对于加拿大葡萄酒行业来说，它仍然至关重要，2011年批准的Icewines价值1亿美元。生产这些葡萄酒为进行发酵的葡萄酒酵母带来了许多挑战。 冰葡萄酒中的溶质将酒酵母放置在增加的高渗胁迫下，导致代谢改变，发酵困难和十倍的含量葡萄酒中发现的乙酸的浓度。 由于它与葡萄酒变质的关系，因此在冰河中高浓度的乙酸是一个问题。 葡萄酒酵母菌菌株显示出不同于研究实验室酵母菌菌株的特性，这些差异可能会影响葡萄酒的有机摄影特性。 但是，这些差异的分子基础在很大程度上仍然未知。 该计划的中心研究目标是在分子水平上获得更全面的理解，即在浓缩葡萄汁发酵过程中影响葡萄酒酵母应力反应的因素，以及这些反应与细胞氧化还原平衡，甘油，有机酸的产生和整体葡萄酒质量如何相关。 我们将检查这种影响，而酵母首先适应浓缩冰葡萄酒汁的过度渗透应激，然后在发酵过程中适应乙醇和乙酸应激。 一旦我们了解了为什么在此反应中形成某些代谢产物，就应该可以控制酵母代谢，以避免或最小化不必要的化合物，例如乙酸。 这项研究将为开发最适合冰川和葡萄酒风格的酵母菌菌株提供关键信息，例如在新兴的加拿大苹果酱葡萄酒风格中发现的，该风格由葡萄成熟的外葡萄生产。这些信息将适用于酿酒师，协助他们维持和扩大加拿大在冰河质量方面的全球优势，并在他们分支到涉及高糖汁的新葡萄酒风格中，以支持他们的需求。