Departamento de Tecnologia e Ciência dos Alimentos, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
Departamento de Química, Universidade Federal de Santa Maria, 97105-900 Santa Maria, RS, Brazil.
Food Chem. 2018 Aug 30;258:59-62. doi: 10.1016/j.foodchem.2018.03.028. Epub 2018 Mar 8.
An innovative use of thermal infrared enthalpimetry (TIE) is proposed for the determination of alcoholic content of red and white wines. Notwithstanding the presence of ethanol in beverages, absolute ethanol was added directly to wines, and the temperature rise caused by the heat of dilution was monitored using an infrared camera. Analytical signals were obtained in only 10 s for four samples simultaneously, and a calibration curve was constructed with hydroalcoholic reference solutions. A linear calibration curve was obtained from 3.0 to 18.0% (v/v) ethanol (R = 0.9987). The results showed agreement ranging from 98.2 to 104.0% with 942.06 and 969.12 methods of AOAC. Organic compounds (e.g., sugar) did not interfere in the determinations. The proposed method provided fast results, with a throughput of 480 samples per hour and negligible energy consumption (0.001 kWh). In addition, the consumption of reagents was reduced when compared with conventional method fulfilling green analytical chemistry requirements.
本文提出了一种利用热红外焓法（TIE）测定红葡萄酒和白葡萄酒中酒精含量的创新方法。尽管饮料中存在乙醇，但仍直接向葡萄酒中添加绝对乙醇，并使用红外摄像机监测稀释热引起的温升。对于四个样品，同时在 10s 内获得了分析信号，并使用水醇参考溶液构建了校准曲线。从 3.0 到 18.0%（v/v）乙醇（R=0.9987）获得了线性校准曲线。结果表明，与 AOAC 的 98.2 至 104.0%的 942.06 和 969.12 方法一致。有机化合物（如糖）在测定中没有干扰。该方法快速，每小时可处理 480 个样品，能耗可忽略不计（0.001 kWh）。此外，与传统方法相比，该方法减少了试剂的消耗，符合绿色分析化学的要求。
