Australian Wine Research Institute, P.O. Box 197, Glen Osmond (Adelaide), SA 5064, Australia.
Food Chem. 2012 Dec 15;135(4):2863-71. doi: 10.1016/j.foodchem.2012.06.127. Epub 2012 Jul 15.
Oxygen or lipids are required to complete stressful alcoholic fermentation. Lack of these nutrients can inhibit sugar uptake and growth, which leads to incomplete or 'stuck' fermentation. Oxygen or lipids supplementation not only restores yeast fermentative activity and also affects formation of yeast volatile metabolites. To clarify the effect of oxygen and lipid supplementation on the formation of flavour active metabolites during wine fermentation, we evaluated the addition of these two nutrients to chemically defined grape juice and filter clarified Chardonnay must. Lipid addition increased the concentration of esters, higher alcohols and volatile acids, whereas oxygen increased the concentration of higher alcohols and altered the proportion of acetate to ethyl esters and the proportion of branch-chain acids to medium-chain fatty acids. Combined addition of lipids and oxygen showed an additive effect on concentration of higher alcohols whereas oxygen suppressed the enhancing effect of lipids on formation of esters and volatile acids. Our results demonstrate the potential of lipid and oxygen supplementation for the manipulation of wine aroma in white wine fermentation.
完成应激性酒精发酵需要氧气或脂质。缺乏这些营养物质会抑制糖的摄取和生长，从而导致发酵不完全或“停滞”。氧气或脂质的补充不仅可以恢复酵母的发酵活性，还会影响酵母挥发性代谢物的形成。为了阐明在葡萄酒发酵过程中补充氧气和脂质对风味活性代谢物形成的影响，我们评估了向化学定义的葡萄汁和过滤澄清的霞多丽葡萄汁中添加这两种营养物质的效果。脂质的添加增加了酯类、高级醇和挥发性酸的浓度，而氧气的添加增加了高级醇的浓度，并改变了乙酸酯与乙酯的比例以及支链酸与中链脂肪酸的比例。脂质和氧气的联合添加对高级醇的浓度表现出相加效应，而氧气抑制了脂质对酯类和挥发性酸形成的增强作用。我们的结果表明，脂质和氧气的补充有可能用于控制白葡萄酒发酵过程中的葡萄酒香气。
