Alcohol Determination of Malt-Based Beverages by Rapid Distillation

Abstract

ABSTRACTThe objective of the study was to assess a rapid distillation unit as an alternative to standard distillation (Beer-4A). A rapid distillation unit (Vapodest 200 by Gerhardt Analytical Systems) was selected as an alternative for its ability to rapidly distill using the power of steam. The NIR/density method (Beer-4G) is quite suitable for measuring the alcohol content of beer; however, flavored malt beverages present a challenge. Deviations between results by the NIR/density method versus results by distillation can occur due to flavor additions and/or high alcohol content. A more accurate way to measure alcohol in this type of product is to first perform a standard distillation (Beer-4A). Unfortunately, this method is time consuming and labor intensive. A precision study was performed to determine repeatability and reproducibility. Three analysts distilled five malt-based products including both beer and flavored malt beverages with alcohol levels ranging from 4.2 to 14.4% (v/v). Repeatability and reproducibility coefficients of variation for the determination of alcohol for this range were 0.05–0.23% and 0.11–0.19%, respectively. In addition, results from Beer-4A and rapid distillation were assessed using a paired t test for alcohol levels ranging from 3.6 to 14.4% (v/v). The P value of 0.30 indicated that there was not a statistically significant difference between the means of the data sets at a 95% confidence level.