Stonys D B
J Assoc Off Anal Chem. 1987 Jan-Feb;70(1):114-7.
A rapid, sensitive polarographic method is presented for determining sulfiting agents in foods and beverages. The method is based on the modified Monier-Williams distillation followed by polarographic detection by differential pulse polarography or square wave voltammetry. A clearly defined wave is obtained by both techniques, with a current maximum at a potential (E) of about -600 mV vs an Ag/AgCl reference electrode. The reaction is based on the reduction of sulfur dioxide at a dropping mercury electrode. Peak current was linear over the range 0-20 micrograms/mL. Quantitation is done by linear regression analysis of standard addition data or by using a standard calibration graph. Screening levels of less than 1 ppm total SO2 were easily achieved in the foods analyzed, which had levels from less than 1 ppm (cereals) to thousands of parts per million (dried fruit). Recoveries from fortified samples ranged from 70 to 108% at fortification levels of 20, 100, and 1000 micrograms/g.
本文介绍了一种快速、灵敏的极谱法，用于测定食品和饮料中的亚硫酸盐。该方法基于改良的莫尼尔-威廉姆斯蒸馏法，随后通过差分脉冲极谱法或方波伏安法进行极谱检测。两种技术均获得了明确的波峰，相对于银/氯化银参比电极，在约-600 mV的电位（E）处出现电流最大值。该反应基于在滴汞电极上二氧化硫的还原。峰电流在0-20微克/毫升范围内呈线性。通过标准加入数据的线性回归分析或使用标准校准曲线进行定量。在所分析的食品中，总二氧化硫含量低于1 ppm的筛选水平很容易实现，这些食品的含量范围从低于1 ppm（谷物）到数千ppm（干果）。在20、100和1000微克/克的强化水平下，强化样品的回收率在70%至108%之间。
