盐酸副玫瑰苯胺分光光度法测定食糖中的亚硫酸盐

Measurement of Sulfite in Granulated Sugar by Spectrophotometry of Pararosaniline Hydrochloride

采用GB/T5009.34-2003四氯汞钠吸收——盐酸副玫瑰苯胺分光光度法对食糖中亚硫酸盐含量进行测定,系统分析该法测定中存在的干扰并探讨盐酸副玫瑰苯胺溶液中盐酸浓度、显色时间、反应温度、溶液颜色深样品前处理等环节对实验结果的影响,得出盐酸浓度0.70~1.00 mol/L,显色温度25℃和显色时间20 min为最佳测定条件,使实验结果更准确、重现性更好。

The sulfite content of the granulated sugar was tested by GB/T5009.34-2003 mercuric sodium tetrachloride absorption-pararosaniline hydrochloride spectrophotometric method.The pH of solution,the reaction time,the reaction temperature,the pre-treatment of sample and other aspects were investigated.The method had good repeatability and more accurate experimental result under the best test condition that the concentration of sulphur diox idew ithin 0.70~1.00 mol/L,the reaction time was 20 min and the reaction temperature was 25 ℃.