Validation Study on Spectrophotometric Measurement of Ethanol from Beer and Non-Alcoholic Beer Samples Distilled by Micro Steam Distillation Method

In this study, a new spectrophotometric method based on the oxidation of sodium dichromate was proposed for the determination of ethanol percentage (v/v) in beer and non-alcoholic beer after distillation with the micro water vapor method, and the method was validated with various parameters. The Harmonized Guidelines for Single-Laboratory Validation of Methods of Analysis were used to validate the analytical method we provided. The following aspects of the method were assessed: precision, recovery, linearity, measuring range, limit of detection (LOD), limit of quantification (LOQ), method detection limit (MDL), and measurement uncertainty. The LOD, LOQ, and MDL values obtained for ethanol were 0.04%, 0.05%, and 0.15%, respectively. The relative standard deviation (RSD) values were less than 2.36% and 4.12% for both repeatability and within-laboratory reproducibility, respectively. Recovery percentages of analytes added to the sample at certain levels were determined to be quantitative between 97% and 102%. These findings fulfill the minimal performance standards outlined in AOAC Official Methods of Analysis Appendix F: Guidelines for Standard Method Performance Requirements. In conclusion, the method validated with various parameters in this study has proven to be effectively usable for the routine analysis of ethanol in beer and non-alcoholic beer. This developed analysis method stands out as an innovative approach in terms of collecting ethanol from beers with the help of micro-distillation water vapor and measuring the color resulting from oxidation.