ORP阶段性控制提高葡萄酒中链脂肪酸乙酯和高级醇含量研究

Increasing Medium-chain Fatty Acid Ethyl Esters and Higher Alcohols in Wine with Phased Control of Oxidation-reduction Potential

摘要:

氧化还原电位（Oxidation-reduction potential, ORP）反映了发酵系统的氧化还原状态，与酵母代谢以及香气化合物合成密切相关，其水平在各酒精发酵阶段存在差异。为了实现ORP在不同发酵阶段的科学控制，通过气相色谱-质谱（Gas chromatography-mass spectrometry, GC-MS）和感官量化分析法在葡萄酒酒精发酵的不同阶段控制不同水平的ORP，观察酵母生长、香气化合物合成以及感官品质的变化。结果表明，在0～48h阶段ORP的变化对酵母活菌数和香气化合物含量的影响远高于其他阶段。提高此阶段ORP有利于酵母生长和糖消耗，而较低ORP有利于香气化合物合成。与对照相比，0mV（0～48h）-自然条件（48～96h）-自然条件（96h至发酵结束）处理组可显著提高中链脂肪酸乙酯中的己酸乙酯、癸酸乙酯含量；0mV-0mV-60mV处理组可显著提高乙酸酯含量；60mV-0mV-60mV处理组可显著提高高级醇含量。0mV-自然条件-自然条件处理增强了赤霞珠葡萄酒中红色水果香气和爱格丽葡萄酒花果类香气，并减弱了爱格丽葡萄酒的动物类气味。ORP的阶段性控制为葡萄酒发酵过程的精准调控提供了依据，为提高葡萄酒香气化合物含量以改善葡萄酒的香气质量提供了基础。

Abstract:

The oxidation-reduction potential (ORP) reflects the oxidation reduction state of the fermentation system, which is closely related to yeast metabolism and aroma compound synthesis, and the ORP level varies during each phase of alcohol fermentation. In order to realize the effective control of ORP in different fermentation phases, different levels of ORP were controlled during different phases of wine alcohol fermentation, and the effects on yeast growth, aroma compound aroma compound synthesis and sensory quality were observed by gas chromatography-mass spectrometry (GC-MS) and sensory quantitative analysis. Results showed that during 0～48h, the number of viable yeast and the content of aroma compounds in yeast were greatly affected by the change of ORP than other fermentation phases. Increasing ORP at this phase was beneficial to yeast growth and sugar consumption, while reducing ORP was beneficial to the synthesis of aroma compounds. Compared with the control, at the level of 0mV (0～48h)-natural conditions (48～96h)-natural conditions (96h to the end of fermentation), the contents of ethyl hexanoate and ethyl decanoate can be significantly increased. The content of acetates can be significantly increased at the level of 0mV-0mV-60mV, and the content of higher alcohols can be significantly increased at the level of 60mV-0mV-60mV. The treatment of 0mV-natural conditions-natural conditions enhanced the aroma of red fruits in Cabernet Sauvignon wine and the fragrance of flowers and fruits in Ecolly wine, while weakened the odor of animals in Ecolly wine. The phased control of ORP provided a basis for the precise regulation of wine fermentation, and laid a foundation for improving the aroma quality of wine by increasing the content of aroma compounds in wine.