Rapid Determination of Ethanol in Non-Alcoholic Malt Beverage by ATR-FT-IR Spectroscopy and Headspace Gas Chromatography Confirmation

Abstract

Malt beverage is one of the most popular drinks in the world. Recently, consumption of non-alcoholic beverages has expanded significantly in many countries. The permitted level of alcohol in malt beverage is less than 0.5% by Iranian National Standards. In this study, a method was developed to determine ethanol content in malt beverages by FTIR, equipped with Horizontal Attenuated Total Reflectance (H-ATR). Here, the Limit Of Detection (LOD) and Limit Of Quantification (LOQ) were 0.07% and 0.23%, respectively. The correlation coefficient of calibration curve was higher than 0.999. Fifty commercial malt beverages from six brands (five Iranian and one imported brand) and three types of flavored malt beverage (classic, equatorial, and lemon) were assessed. The average detected ethanol amount in samples was 0.19%, varying between 0.00-1.47percent. The results showed that the amount of ethanol in lemon malt drinks was more than the maximum permitted limit; that could be attributed to the usage of ethylene glycol for extraction of lemon flavor.