分光光度法测定小麦面粉中过氧化苯甲酰含量

目的]用分光光度法测定面粉及面制品中过氧化苯甲酰含量。方法]在磷酸介质中,过氧化苯甲酰氧化碘化钾生成的碘与淀粉显色,在520 nm波长处有最大吸收峰,建立了淀粉碘化钾体系光度法间接测定微量过氧化苯甲酰的方法。结果]面粉用无水乙醇溶解通过离心提取过氧化苯甲酰,过氧化苯甲酰的质量浓度在0.032 g/L以内呈线性。结论]该方法应用于新制小麦面粉中过氧化苯甲酰的测定,回收率在94.3%以上,步骤简单,易操作,现象明显。

Determination of Benzoyl Peroxide Content in Wheat Flour Based on Spectrophotometry

Objective]The aim was to determine benzoyl peroxide content in wheat flour and flour products based on spectrophotometry.Method]In phosphoric acid medium,potassium iodide oxidized by benzoyl peroxide oxidation,then generated colored iodine and starch,there was maximum absorption peak in 585 nm wavelength,thereby,the starch potassium iodide system spectrophotometry was established to determine benzoyl peroxide.Result]Flour dissolved by ethanol extraction through centrifugal benzoyl peroxid,benzoyl peroxide concentration in the 0.032 g/L or less linearly.Conclusion]The new method has been applied to wheat flour produced in the determination of benzoyl peroxide,and the recovery is 94.3% and above.The experimental results show that the steps of the method is simple and easy to operate,the phenomenon is obvious.