流动注射分析法测定甜型葡萄酒中总二氧化硫

Determination of Total Sulfur Dioxide in Sweet Wine by Flow Injection Analyzer

建立直接测定甜型葡萄酒中高浓度总二氧化硫的微流-连续流动注射分析方法。样品用10%的硫酸酸化,在酸性条件下蒸馏,蒸馏液与甲醛和碱性品红反应生成红色络合物,吸取样品并配制好相应试剂后,采用微流-连续流动分析仪在560 nm波长处自动完成分析。对影响测定的酸化液浓度、碱性品红和甲醛浓度等进行了优化,确定了最佳试验参数。结果显示,二氧化硫标准溶液在25~250 mg/L范围内可呈现良好的线性,线性相关系数大于0.999,检出限为4.6 mg/L,起泡葡萄酒样品加标回收率在92.4%~108.8%范围内,相对标准偏差≤5.3%(n=6)。该方法为甜型葡萄酒中高浓度二氧化硫的直接测定提供了一个自动化、高效、准确的快速检测方法。

Develop a simple and direct method for the direct determination of high concentration of total sulfur dioxide in wine by using micro flow-continuous flow injection analyzer. The sample was diluted in a 10% sulfuric acid solution. After distillation, distillate reacted with formaldehyde and pararosaniline to form a red colored complex which was measured at 560 nm. Analysis was automatically completed by continue flow analysis when the samples and reagents were prepared. The acidification concentration, alkaline fuchsin and formaldehyde concentration were optimized. The results showed that it had a good linear in the range of 25~250 mg/L, the linear correlation coefficient was greater than 0.999, and the limit of determination was 4.6 mg/L. The recoveries of the sparking wine were in the range of 92.4%-108.8%, and the relative standard deviation （RSD） was less than 5.3% （n=6）. Continuous flow analyzer had a very good accuracy and repeatability when estimating total sulfur dioxide in sweet wine, and was a highly automated, effective and fast-speed analysis method.