We introduce an application that analyzes ethanol in alcoholic beverages, taking beer, liqueur, and Japanese sake as the samples. For beverages containing 1 % or more alcohol, there is a requirement to indicate the type of liquor and the concentration of alcohol. The National Tax Agency (NTA) prescribes various methods for ethanol analysis. The GC method among them is able to handle various types of alcoholic beverages, and has the advantage that analysis of components other than alcohol can also be performed by changing the conditions. For the GC method prescribed by NTA, isothermal analysis with a column oven condition at 50 °C is specified. However, since the water and high-boiling-point components in the liquor are not eluted from the column during isothermal analysis at 50 °C, it is not possible to perform a favorable analysis without expelling them by raising the oven temperature after elution of the ethanol and internal standard substances. In addition, since the major component of liquors is moisture, the amount and position of the wool in the insert need to be fine-tuned.
In this article, we introduce a method we developed to make it possible to perform analysis in accordance with the NTA's ethanol analysis favorably in a short time.