The Method for Direct Gas Chromatographic Determination of Acetaldehyde, Methanol, and Other Volatiles Using Ethanol as a Reference Substance: Application for a Wide Range of Alcoholic Beverages

Abstract

The article presents the results of collaborative study of the method for gas chromatographic determination of alcoholic fermentation volatile by-products (acetaldehyde, methanol, methyl acetate, ethyl acetate, propan-2-ol, propan-1-ol, 2-methylpropan-1-ol, butan-1-ol, and 3-methylbutan-1-ol) in alcoholic beverages with volume ethanol content in a range of 9.9–96.0% (wine, sake, liquor, tequila, vodka, grappa, bourbon, scotch, calvados, rakia, rum, brandy, whiskey, gin, and rectified ethyl alcohol). The zest of the method is the use of ethanol, present in beverages, as a reference substance for quantitative determination of mentioned components. Checking of precision data, obtained under repeatability conditions and under both repeatability and intermediate precision conditions, and trueness of test results, was carried out according to the ISO 5725–6. The relative difference between calibration coefficients (relative response factors for analyzed volatile compound relative to ethanol), obtained with an interval of 3 weeks, did not exceed 1.1%. Contents of acetaldehyde, methanol, and volatiles in 15 commercial alcoholic beverages analyzed by the developed method varied in the 1.84–677 mg L⁻¹ of absolute ethanol, 3.25–12,394 mg L⁻¹ of absolute ethanol, and 1.49–4243 mg L⁻¹ of absolute ethanol intervals, correspondingly.