Phouthavong Vanpaseuth, Inoue Hayato, Phomkeona Kesiny, Chounlamany Vanseng
Department of Chemistry, Faculty of Natural Sciences, National University of Laos, P.O. Box 7322, Vientiane, Laos.
Department of Environmental and Life Sciences, Toyohashi University of Technology, 1-1 Hibarigaoka Tempaku-cho, Toyohashi, Aichi 441-8580, Japan.
J Anal Methods Chem. 2022 Mar 31;2022:7346253. doi: 10.1155/2022/7346253. eCollection 2022.
This work utilized the simplicity of a so-called membraneless vaporization (MBL-VP) unit as a gas separator for the colorimetric determination of ethanol in alcoholic beverages. A beverage sample with a volume of 1 mL was directly injected into a small container which was hung from a lid inside a closed 40 mL reused glass bottle without pretreatment such as distillation. An acidified potassium dichromate (CrO ) acceptor solution, preadded to the glass bottle, was reduced to Chromium (III) ion by the diffusion of vaporized ethanol from the sample. After 5 min, the absorbing solution was collected for colorimetric detection at 590 nm. The unit manually quantifies ethanol in the range 1.0-90% (v/v) with satisfactory interday precision but without matrix effect (recovery 89-109%). The method was validated with the conventional distillation/pycnometer method which showed no significant difference of ethanol contents between those two methods and the declared values of 12 alcoholic beverages, indicating sufficient accuracy. Analyses of alcoholic beverages using this method were successful with benefits of simplicity, cheapness, and less energy consumption.
这项工作利用了所谓的无膜汽化（MBL-VP）装置的简易性，将其作为一种气体分离器，用于比色法测定酒精饮料中的乙醇。将1 mL体积的饮料样品直接注入一个小容器中，该小容器悬挂在一个封闭的40 mL可重复使用玻璃瓶内的盖子上，无需进行蒸馏等预处理。预先添加到玻璃瓶中的酸化重铬酸钾（CrO）接受溶液，通过样品中汽化乙醇的扩散被还原为铬（III）离子。5分钟后，收集吸收溶液用于在590 nm处进行比色检测。该装置可手动定量1.0-90%（v/v）范围内的乙醇，日间精密度令人满意且无基质效应（回收率89-109%）。该方法通过传统蒸馏/比重瓶法进行了验证，结果表明这两种方法测得的乙醇含量与12种酒精饮料的标称值之间无显著差异，表明该方法具有足够的准确性。使用该方法对酒精饮料进行分析取得了成功，具有操作简单、成本低廉和能耗较低的优点。
