Microoxygenation (Mox) is widely used in winemaking to improve color, in-mouth properties and aroma, but its use is not always predictable. Here we investigate the effect of Mox, (while monitoring viable yeasts and SO₂ levels), on color, anthocyanin-derived pigments, tannins, aroma and in-mouth sensory properties as well as on hedonic rating by wine experts. Results on this Merlot wine show that the re-appearance of viable Saccharomyces cerevisiae yeasts modulates oxygen consumption rates, and dramatically increases acetaldehyde levels. This led to significant sensory changes, particularly for aroma. Mox reduced green-vegetable and reduction-related aromas, but also astringent mouth-feel properties related to tannins, and lower astringency was correlated with lower tannin activity. The Mox wines that exhibited yeast growth had higher hedonic scores from one group of expert tasters based on increased jammy/dried fruit flavors, while another group of tasters rated the non-Mox wines higher due to the green vegetable and spicy aromas. These results show that the chemical and sensory impact of a Mox treatment is highly dependent on the absence or presence of yeast growth, so it is important to monitor for yeast populations during Mox treatment.

微氧化法（Mox）被广泛用于酿酒中以改善颜色，口内特性和香气，但其使用并非总是可预测的。在这里，我们研究了Mox（同时监测活酵母和SO _2的水平）对颜色，花青素衍生的色素，单宁，香气和口中感官特性以及酒专家对享乐主义等级的影响。这款美乐葡萄酒的结果表明，有活力的酿酒酵母得以重现酵母调节耗氧率，并显着提高乙醛水平。这导致明显的感官变化，尤其是对于香气。Mox减少了绿色蔬菜和与还原有关的香气，但同时也降低了与单宁有关的口感，而较低的涩味与较低的单宁活性相关。表现出酵母生长的Mox葡萄酒在果酱和干果风味增加的基础上，一组专家品尝者的享乐分数较高，而另一组品尝者则由于绿色蔬菜和辛辣香气而对非Mox葡萄酒的评价较高。这些结果表明，Mox处理的化学和感官影响高度依赖于酵母生长的存在与否，因此在Mox处理过程中监测酵母种群非常重要。