不同窖龄窖池酿造浓香型基酒的风味差异分析

Differences in Flavor Profiles of Luzhou-Flavor Base Baijiu from Different Aged Cellars

为探究不同窖龄窖池酿造浓香型基酒的物质构成和含量分布规律,采用直接进样、液液萃取、表面活性剂/涡旋辅助液液微萃取结合气相色谱、气相色谱-质谱技术对3个不同窖龄窖池生产的18种浓香型基酒中的风味成分进行定性、定量分析;引入主成分分析、偏最小二乘判别分析以及Spearman相关系数法等化学计量方法解构不同基酒酒样间的风味差异。结果表明:在新窖池、30 a以上窖龄窖池、100 a以上窖龄窖池3类不同窖龄窖池生产的18个基酒中分别定性出151、154种和159种挥发性化合物,其中相同类型化合物共148种,占全部已测出化合物总数的93.1%;对其中61种重要风味化合物进行定量分析,己酸乙酯、丁酸乙酯、己酸、丁酸和乙酸在3个不同窖龄窖池酒样中的质量浓度均超过100 mg/L,其中己酸乙酯的质量浓度最高,为1156.4~2142.2 mg/L;化学计量学结果显示,相较于100 a以上窖龄窖池酿造的基酒,新窖池与30 a以上窖龄窖池酿造的2种基酒中风味化合物间的相似度更高,相关研究结果为行业对浓香型白酒窖龄影响酒体风味惯有经验认知提供了一定的数据支撑和进一步验证。

To investigate the distribution of flavor components in Luzhou-flavor base Baijiu from different aged cellars,the aroma components in 18 samples of Luzhou-flavor base Baijiu from three cellars of different ages were identified and quantified by direct injection(DI),liquid-liquid extraction(LLE)or vortex-assisted surfactant-enhanced emulsification liquid-liquid microextraction(VSLLME)combined with gas chromatography(GC)and gas chromatography-mass spectrometry(GC-MS).The differences in flavor among different base Baijiu samples was analyzed by chemometrics methods such as principal component analysis(PCA),partial least squares-discriminant analysis(PLS-DA),and Spearman’s correlation coefficient.The results suggested that 151,154 and 159 volatile compounds were identified in base Baijiu from freshly prepared cellar and those aged over 30 and 100 years.In total,148 aroma compounds were common to the three base Baijiu,accounting for 93.1%of the total number of identified compounds.The quantitative analysis of 61 major aroma compounds showed that the concentrations of ethyl caproate,ethyl butyrate,hexanoic acid,butyric acid and acetic acid in base Baijiu from each cellar exceeded 100 mg/L.The concentration of ethyl caproate was the highest,ranging from 1156.4 to 2142.2 mg/L.Chemometric results indicated that the flavor similarity of base Baijiu between the new and over-30-year-old cellars was higher when compared with the cellar aged over 100 years.This findings further strengthen the Baijiu industry’s conventional knowledge of the influence of cellar age on the flavor of Luzhou-flavor Baijiu.