微波消解—离子色谱法测定面制品中磷酸盐含量

Determination of phosphate in wheat flour products by microwave digestion-ion chromatography

为建立用微波消解进行样品前处理，离子色谱法测定面制品中的磷酸盐含量的检测方法。用离子色谱带电导检测器进行分离测定，色谱柱为IonPac AS19（4×250mm），35mmol／L氢氧化钾为淋洗液，流速为1．0mL／min。结果表明加标回收率在97．0％～115．O％范围，相对标准偏差均小于0．5％，在1．0～50．0mg／L范围呈现良好的线性关系，回归系数大于0．999。该法具有操作简便、分析快速、准确等优点，能满足面制品中磷酸盐含量检测要求。

Phosphate in wheat flour products, which was pretreated by microwave digestion technique, was determined by ion chromatography equipped with a conductivity detector. The chromatographic col- umn was IonPac AS19（4 ×250 mm）and the mobile phase was 35 mmol/L KOH solution at a flow rate of 1.0 mL/min. The result showed that the recovery rate for this method was 97.0%- 115.0% and the telative standard deviation was less than 0.5% . The linear regression coefficientwas higher than 0. 999 within the concentration range of 1.0 - 50.0 mg/L. As a simple and rapid testing, this method showed satisfied accuracy and was suitable for the determination of phosphate in wheat flour products.