Using Raman Spectroscopy for Determination Methanol Quantity in Illegal Alcoholic Beverages

Illegal production of alcoholic beverages is a common problem in most countries. The consumption of these counterfeit alcoholic products in Turkey has increasingly been one of the major health concerns. In this study, a comparison between GC-MS and Raman spectroscopy techniques was made to determine the amount of methanol in BogmaRaki which is a counterfeit alcoholic beverage produced and consumed in Hatay region. Different ratios of methanol/ethanol concentrations were prepared to obtain a calibration curve. This curve was used to measure the amount of methanol in the actual product samples using both GC-MS and Raman spectroscopy techniques. Results obtained from both techniques were compared using Paired sample t-tests. The Limit of Detection and the Limit of Quantification values were determined as 0. 03 (%v/v) and 0. 11 (v/v), respectively. Both techniques demonstrated a similar sensitivity in the determination of methanol concentration in these counterfeit products (p>0.05). Raman Spectroscopy, however, has an advantage of being easy to use, inexpensive, rapid and non-destructive analytical technique with little or no sample preparation.