面粉及面制品中过氧化苯甲酰的二极管阵列检测-高效液相色谱测定法

Determination of Benzoyl Peroxide in Flour and Flour Products with Diode Array Detector of High Performance Liquid Chromatography

目的研究检测面粉及面制品样品中过氧化苯甲酰含量的前处理及测定方法,并对市售面粉及面制品中过氧化苯甲酰添加状况进行调查。方法用乙醇提取面粉及面制品中过氧化苯甲酰,碘化钾还原过氧化苯甲酰为苯甲酸,以高效液相色谱法二极管阵列检测器测定其含量,色谱条件:流动相为0.02mol/LNH4Ac水溶液∶甲醇(96∶4),流速1.20ml/min,柱温40℃,检测波长225nm,进样量为10μl。结果方法检出限为0.005mg(以3倍噪声值计),回收率在97.0%～100.7%之间,精密度为1.21%(低浓度)和0.44%(高浓度)。调查147份面粉和102份面制品样品,阳性率84.3%,超标率29.3%,面制品超标率高于面粉。结论该方法测定面粉及制品中过氧化苯甲酰具有操作简单、干扰少、准确可靠等特点,可以在日常检测工作中推广;面制品用面粉过氧化苯甲酰卫生标准进行评价不合适,应采用食品中防腐剂苯甲酸的卫生标准。

[Objective] To explore an effective method for determining benzoyl peroxide in flour and flour products. [Methods] The benzoyl peroxide in flour and flour products was extracted with anhydrous alcohol; its content was determined with diode array detector of high performance liquid chromatography. The optimized condition of HPLC was as follow: eluting solvent was V (0.02mol/L NH 4Ac) LV (methanol) =96:4, eluting rate was 0.20ml/min, column temperature was 40℃, wavelength of detection was 225nm, injecting volume was 10μl. [Results] The detection limit of the method was 0.005 mg; the recovery rate was between 97.0% and 100.7%; RSD was 0.21% (low concentration) and 0.44% (high concentration). Among the 249 samples of flour and flour products, the positive rate of benzoyl peroxide was 84.3%, and 29.3% of them were found with super scale over the hygienic standard, the superscale in flour products was higher than that in the flour. [Conclusion] This method is accurate and easy to operate in determining benzoyl peroxide in flour and flour products. The hygienic standard for antiseptic benzoic acid should be used to determine the flour products.