Abstract:

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.

Key words: gas chromatography, Dukang liquor base liquor, typical flavor substances