The amount of ethanol in beverages has been quantified by density and infrared spectroscopy methods. The density method allows only the amount of ethanol to be quantified, while the infrared spectroscopy method allows the quantification of ethanol and, if any, the presence of contaminants such as methanol. The amount of ethanol quantified agrees to bottle declaration particularly for the infrared spectroscopy method. The infrared spectroscopy method coupled with a mathematical treatment (PCA and PLS-2) thus distinguishes itself as a fast and reliable technique for determining the amount of ethanol in beverages.