离子色谱法测定海产品中亚硫酸盐残留量

Determination of Sulphite Residue in Seafood by Ion Chromatography

建立蒸馏／离子色谱法测定海产品中亚硫酸盐残留的分析方法。粉碎后的样品在酸性条件下进行水蒸汽蒸馏，用含1％甲醛的碱性溶液作为吸收液，馏出液过0．22μm滤膜后，进离子色谱仪检测，外标法定量。以H，0／100mmol／LNaOH为淋洗液，IonPacASll—HC阴离子色谱柱分离，电导检测器进行检测。实验结果表明，SO32-在0．5～50mg／L范围内线性关系良好（r2=0．9993），检出限（LOD）为1．0mg／kg，回收率为84．5％-101．3％。本方法具有快速、简便、精密度高及重现性好等优点，适用于海产品中亚硫酸盐的测定。

A method to determine sulphite residue in seafood with ion chromatography and steam distillation were studied. The crushed sample was extracted by steam distillation under acidic conditions and absorbed by 1% formaldehyde alkaline solution. The distillate was filtered by a 0.22 μm membrane; then it was analyzed by ion chromatography with electrical conductivity detector and quantified by external standard method. H20/100 mmoL/L NaOH was used as mobile phase, and IonPac AS11 - HC column was selected as the separation column. The signal was detected with electrical conductivity detector. The result showed that the standard curves of sulphite content were linear in the concentration ranged from 0.5 to 50 mg/L with correlation coefficients of 0. 999 3. The limit of detection was 1.0 mg/kg and the recovery ranged from 84.4% to 101.4%. With rapid and simple operation, high precision and good repeatability, this method is suitable for determination of sulfite in seafood.