College of Enology, Northwest A&F University, Yangling, Shaanxi 712100, China.
College of Enology, Northwest A&F University, Yangling, Shaanxi 712100, China; Ningxia Helan Mountain's East Foothill Wine Experiment and Demonstration Station of Northwest A&F University, Yongning, Ningxia 750104, China.
Food Res Int. 2022 Jul;157:111369. doi: 10.1016/j.foodres.2022.111369. Epub 2022 May 16.
The medium-chain fatty acid ethyl esters (MCFAEEs) are a group of important aroma compounds generated during wine production. Wine alcohol fermentation involves several redox processes, which are affected by the oxidation-reduction potential (ORP). However, the mechanism via which ORP regulates MCFAEE production remains unclear. To investigate the effect of ORP on MCFAEE production, wine alcohol fermentation was performed using Saccharomyces cerevisiae under different ORPs. The results demonstrated that the ORPs studied (except for 90 mV) did not significantly affect cell growth, sugar consumption, and ethanol production, while the MCFAEE concentration in the simulated wines can be manipulated by ORP operation. MCFAEE levels increased till 96 h, and then decreased. The maximum MCFAEE level of 1222.97 μg/L was obtained after 96 h at 0 mV, which was 45.32% higher than that of the control. During the increase, higher relative expression of ACC1, FAS1, FAA2 and EEB1, elevated external citric acid flux, and moderate intracellular NADP/NADPH ratio were observed at 0 mV compared to that at other ORPs. During the decrease, lowest relative expression of POX1 was detected at 0 mV. We showed for the first time the relationship between ORP operation and MCFAEE production in winemaking, which will improve the aroma quality of wine.
中链脂肪酸乙酯（MCFAEEs）是葡萄酒生产过程中产生的一组重要香气化合物。葡萄酒酒精发酵涉及多个氧化还原过程，这些过程受氧化还原电位（ORP）的影响。然而，ORP 调节 MCFAEE 产生的机制尚不清楚。为了研究 ORP 对 MCFAEE 产生的影响，使用酿酒酵母在不同的 ORP 下进行了葡萄酒酒精发酵。结果表明，所研究的 ORP（除 90 mV 外）对细胞生长、糖消耗和乙醇生产没有显著影响，而 ORP 操作可以控制模拟酒中的 MCFAEE 浓度。MCFAEE 水平在 96 小时内增加，然后减少。在 0 mV 下，经过 96 小时后，MCFAEE 水平达到 1222.97μg/L 的最大值，比对照提高了 45.32%。在增加过程中，与其他 ORP 相比，在 0 mV 下观察到 ACC1、FAS1、FAA2 和 EEB1 的相对表达更高，柠檬酸外通量增加，细胞内 NADP/NADPH 比值适中。在减少过程中，在 0 mV 下检测到 POX1 的相对表达最低。我们首次展示了 ORP 操作与葡萄酒酿造中 MCFAEE 产生之间的关系，这将提高葡萄酒的香气质量。
