离子色谱法测定小麦粉中溴酸钾和过氧化苯甲酰

Detection of Potassium Bromate and Benzoyl Peroxide in Wheat Flour by Ion Chromatography

建立了离子色谱快速同时检测小麦粉中溴酸钾和过氧化苯甲酰添加剂含量的分析方法。样品经100℃加热反应45min处理后，通过水提取，采用Supp5-250离子色谱柱；以5mmol／L Na2CO3-乙腈作为流动相，在流速为0．6ml／min时进行等度洗脱，室温条件下分离待测物，并用化学抑制电导检测。结果显示，在选定色谱条件下溴酸根和苯甲酸根有效分离，且线性关系良好，溴酸钾回收率为97．0％～98．8％，过氧化苯甲酰回收率为92．5％～107．5％。表明该方法快速、准确，能同时测定小麦粉中溴酸钾和过氧化苯甲酰添加剂的含量。

A rapid and simultaneous analysis method by ion chromatography for detection of additives potassium bromate and benzoyl peroxide in wheat flour was established. The samples were extracted by water after reaction under 100℃ for 45 min by means of Supp 5 -250 ion chromatographic column; taking 5 mmol/L Na2CO3 - acetonitrile as a flow phase, isocratic elution was carried out under flow rate of 0.6 ml/min, and the product to be detected was separated under room temperature and detected by chemical inhibi- tion electric conductance. The results indicated that the bromic acid radical and benzoic acid radical were separated effectively under the selected chromatography, presenting a good linear relation, and recovery rate of potassium bromate was 97.0% -98.8% and recovery rate of benzoyl peroxide was 92.5% ～ 107.5%. These indicated that this method could detect the additive contents of potassium bromate and benzoyl peroxide in wheat flour rapidly, accurately and simultaneously.