小曲清香型白酒中关键风味成分分析

采用气相色谱-质谱-嗅闻分析、顶空固相微萃取-气相色谱-质谱联用技术对不同质量等级的小曲清香型白酒样品进行全面定性与定量分析，明确不同质量等级小曲清香型白酒的关键性风味成分，继而利用多元统计学方法对2 种小曲清香型白酒进行差异性分析。结果显示，2 种质量等级的小曲清香型白酒中挥发性香气成分在种类方面具有一定的相似性，但乙酯类风味成分在优级酒中的风味贡献度大于一级酒，而部分高级醇类、硫化物、醛酮类、呋喃类等成分在一级酒中的贡献大于优级酒。基于偏最小二乘判别分析，乙酸乙酯、乳酸乙酯、异丁醇、异戊醇、乙醛等化合物含量在2 种不同质量等级小曲清香型白酒中存在显著差异，这也是导致二者感官评价和风味特征存在显著差异的关键因素。

Analysis of Key Flavor Components in Xiaoqu Mild-flavor Baijiu

The key flavor compounds of Xiaoqu mild-flavor baijiu were qualitatively and quantitatively analyzed by gas chromatography-mass spectrometry-olfactometry (GC-MS-O) and headspace solid phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS). The differences in key flavor compounds between two quality grades of Xiaoqu mild-flavor baijiu were analyzed by multivariate statistics. The results showed that the two quality grades of Xiaoqu mild-flavor baijiu were similar in terms of volatile aroma composition. The contribution of ethyl esters to the flavor of the superior grade was greater than to that of the first grade, while the opposite was observed for some higher alcohols, sulfides, aldehydes and ketones. Partial least squares-discriminant analysis showed that significant differences in the contents of ethyl acetate, ethyl lactate, isobutanol, isoamylol and acetaldehyde existed between the two quality grades of Xiaoqu mild-flavor baijiu, which might be the key factor causing the differences in sensory evaluation and flavor characteristics between them.