Instituto de Fermentaciones Industriales (CSIC), C/Juan de la Cierva 3, 28006 Madrid, Spain.
J Agric Food Chem. 2009 Nov 25;57(22):10784-92. doi: 10.1021/jf900904x.
The characterization of commercial enological inactive dry yeast (IDY) with different applications in wine production has been carried out. This study was based on the yeast's ability to release soluble compounds (high molecular weight nitrogen, free amino nitrogen, peptidic nitrogen, free amino acids, and polysaccharides) into model wines and on its behavior toward the volatility of seven wine aroma compounds. Important differences in soluble compounds released into the model wines supplemented with commercial IDY were found, with the free amino acids being among the most released. The volatility of most of the aroma compounds was affected by the addition of IDY preparations at a concentration usually employed during winemaking. The extent of this effect was dependent on the physicochemical characteristics of the aroma compound and on the length of time the IDY preparations remained in contact with the model wines. Whereas shorter contact times (2, 4, and 6 days) mainly promoted a "salting-out" effect, longer exposure (9 and 13 days) provoked a retention effect, with the consequent reduction of aroma compounds in the headspace. The use of different commercial preparations also promoted different effects toward the aroma compounds that may be at least in part due to differences in their ability to release soluble compounds of yeast origin into the wines.
对具有不同葡萄酒酿造应用的商业酿酒用无活性干酵母（IDY）进行了特性描述。该研究基于酵母将可溶性化合物（高分子量氮、游离氨基酸氮、肽氮、游离氨基酸和多糖）释放到模型葡萄酒中的能力，以及其对七种葡萄酒香气化合物挥发性的行为。在添加商业 IDY 的模型葡萄酒中发现了释放到葡萄酒中的可溶性化合物的重要差异，其中游离氨基酸是释放最多的化合物之一。添加 IDY 制剂（通常在酿酒过程中使用的浓度）会影响大多数香气化合物的挥发性。这种影响的程度取决于香气化合物的物理化学特性以及 IDY 制剂与模型葡萄酒接触的时间长短。较短的接触时间（2、4 和 6 天）主要促进了“盐析”效应，而较长的暴露时间（9 和 13 天）引起了保留效应，导致顶空香气化合物减少。使用不同的商业制剂也会对香气化合物产生不同的影响，这至少部分归因于它们将酵母来源的可溶性化合物释放到葡萄酒中的能力的差异。
