Differential-pulse polarographic microdetermination of ethanol and its application to beer analysis

Abstract

Ethanol, after in situ derivatization to ethyl dithiocarbonate under phase-transfer catalysis, was determined in aqueous solution by differential-pulse polarography. A supporting electrolyte of NH₄Cl—KH₂PO₄—NaOH containing eosin was found to be essential in this determination. For the microdetermination of ethanol, this method was proved to be precise, and the detectionlimit was 0.02% or 0.02 mg (absolute amount of ethanol). The viability of the proposed method for beer analysis has also been established.