白酒基酒典型风味物质含量的测定方法与差异性研究

建立一种新的、同时测定杜康不同级别白酒基酒中11 种典型风味物质含量的气相色谱外标法，采用AT.LZP-930型色谱柱（25 m×0.32 mm，0.1 μm），氢火焰离子检测器检测，进样口温度220 ℃，检测器温度250 ℃，柱流速2.0 mL/min，载气为氮气（纯度99.999%），载气流速30 mL/min，H2流速30 mL/min，空气流速300 mL/min，尾吹流速25 mL/min；采用分流进样方式，分流比10∶1，进样量1 μL。结果表明：该方法简便、准确性高；通过对不同级别白酒基酒中11 种典型风味物质含量的测定与分析，结合品酒师的品评结果可以得出：杜康不同级别中白酒基酒11 种典型风味物质中己酸乙酯、乳酸乙酯、乙酸乙酯、己酸4 种物质的含量差异显著（P＜0.05），其中乙酸乙酯、己酸乙酯、己酸的含量随着级别的降低而显著递减，而乳酸乙酯的含量随着级别的降低而递增，其他7 种物质的含量差异不显著（P＞0.05）；己酸乙酯与乳酸乙酯、己酸乙酯与乙酸乙酯的最佳比例分别在1.2∶1以下和1.7∶1～1.4∶1，己酸含量在160 mg/100 mL时最佳。

Determination and Comparison of the Contents of Typical Flavor Substances in Base Liquor of Dukang,a Chinese Liquor

A new gas chromatographic (GC) method was established to quantitatively analyze 11 typical flavor substances
in liquor base of Dukang, a Chinese liquor, using external standard method. The chromatographic separation was performed
on an AT.LZP-930 column (25 m × 0.32 mm, 0.1 μm) at a flow rate of 2.0 mL/min and detection was done using a flame
ionization detector (FID) at 250 ℃. The injection port temperature was set at 220 ℃. The carrier gas used was nitrogen
(99.999%) at a flow rate of 30 mL/min, the H2 flow rate was 30 mL/min, the air flow rate was 300 mL/min, and the tail wind
velocity was 25 mL/min. The sample injection was conducted in the split mode with a split ratio of 10:1, and the sample
volume was 1 μL. The results indicated that the method was simple and accurate. The contents of 11 typical flavor substances
in liquor base were analyzed and compared. Among these compounds, ethyl caproate, ethyl lactate, ethyl acetate and caproic
acid showed significantly different contents in different grades of liquor base (P < 0.05), and the contents of ethyl acetate,
ethyl caproate and caproic acid were decreased sharply while the content of ethyl lactate was increased with reducing grade.
However, the contents of the remaining seven substances were almost similar in different grades of liquor base. The optimal
proportions of ethyl caproate to ethyl lactate, and ethyl caproate to ethyl acetate were 1.2:1 and 1.7:1–1.4:1, respectively, and
the optimal content of caproic acid was 160 mg/100 mL.