建立了一种检测绿豆芽中亚硫酸盐的含量新方法。绿豆芽在充氮条件下进行蒸馏，挥发出来的SO2用氢氧化钠溶液进行吸收，吸收后的亚硫酸盐在室温下，pH值为6.6的介质中与铵盐、邻苯二甲醛反应生成强荧光物质，荧光强度与亚硫酸盐浓度（以SO2计）在0~9.60 mg/L范围内呈现良好的线性，线性方程为y=403.1x-147.41，相关系数为0.9996。该方法测定豆芽中的亚硫酸盐操作简单，选择性好，灵敏度高，所测结果与国标法（蒸馏滴定法）无显著性差别。同时对豆芽中亚硫酸盐的去除方法进行了研究，考察了水、醋酸水溶液、氯化钠溶液、碳酸钠溶液、洗米水对豆芽中亚硫酸盐的去除效果。结果表明洗米水和碳酸钠水溶液可以很好地去除豆芽中的亚硫酸盐。在65 ℃，绿豆芽在150.00 g/L洗米水和2.00 g/L的碳酸钠溶液中浸泡1.5 h，亚硫酸的去除率可分别达到66.41%~72.83%和67.07%~80.12%。

A new method was established for the determination of sulfite (SO2) content in mung bean sprouts. Mung bean sprouts were distilled with a nitrogen flow, and the volatilized SO2 was absorbed by sodium hydroxide solution. At room temperature, the absorbed sulfite, ammonium salt and ortho-phthalaldehyde (OPA) could react to generate compounds with strong fluorescence in a medium with a pH of 6.6. The fluorescence intensity and concentration of SO2 showed good linearity in the range of 0 to 9.60 mg/L, and the regression equation was y = 403.1x – 147.41, with a correlation coefficient of 0.9996. This method for determination of SO2 content in mung bean sprouts was simple, sensitive, and selective, and the results obtained showed no significant differences from those using the national standard method (the distillation-distillation method). Furthermore, appropriate methods for removal of sulfite in mung bean sprouts were studied. Additionally, the effects of water, acetic acid solution, salt solution, sodium carbonate solution, and rice washing water on removal of SO2 from mung bean sprouts were investigated. The results showed that the sulfite in mung bean sprouts could be effectively removed with rice washing water and sodium carbonate solution. At 65°C, mung bean sprouts were soaked in 150.00 g/L rice washing water and 2.00 g/L sodium carbonate solution for 1.5 h, and the removal rates of SO2 reached 66.41–72.83% and 67.07–80.12%, respectively.

“十二五”国家科技支撑计划（2012BAD29B06）；辽宁省食品安全重点实验室暨辽宁省高校重大科技平台“食品贮藏加工及质量安全控制工程技术研究中心”开放课题（LNSAKF2011024）。