Colorimetric Method for the Estimation of Ethanol in Alcoholic-Drinks

A method for estimating ethanol in alcoholic-drinks by direct reaction is presented. The method consist of color reaction of ethanol with sodium dichromate. The colorimetric quantification was based on the formation of green colored chromate ions resulting from treatment of ethanol and sodium dichromate as limiting reactant in presence of sulfuric acid and acetate buffer pH 4.3. The absorbance maxima for the ethanol was found to be 578 nm. The influence of acetate buffer pH, reaction time, and Beer’law on color development and sensitivity were investigated and optimal assay conditions established.The limits of detection and quantification for ethanol were determined to be 0.6 mg/mL and 1.9 mg/mL