提出了离子色谱法测定食品中添加剂丙酸盐含量的方法。试样用水蒸馏浸取,提取液中的丙酸盐与干扰离子以IonPac AS11-HC(250 mm×4 mm)为分析柱、IonPac AG11-HC(250 mm×4 mm)为保护柱,氢氧化钾溶液梯度洗脱分离并用电导检测器测定丙酸盐的含量。丙酸的质量浓度在20.00~40.00 mg·L-1范围内与峰面积呈线性关系,检出限(3S/N)为1.00 mg·kg-1。方法用于测定粉皮样品中丙酸盐含量,加标回收率在91.3%~96.2%之间,测定值的相对标准偏差(n=12)在0.5%~1.2%之间。

A method of IC was proposed for the determination of the additive propionate in food. The sample was extracted with water by distillation. The propionate and interfering ions in the extract were separated on IonPac AS11-HC (250 mm ×4 mm) column with IonPac AG11 (250 mm ×4 mm) as guard column, by gradient elution with KOH solution of different concentrations as mobile phase and detected by conductivity detector. Linear relationship between values of peak area and mass concentration of propionic acid was kept in the range of 20.00-40.00 mg·L-1, with detection limit (3S/N) of 1.00 mg·kg-1. The present method was applied to the determination of propionate in sample of vermicelli, giving values of recovery ranged from 91.3%-96.2%, and values of RSD′s (n=6) ranged from 0.5%-1.2%.