食品添加剂双乙酸钠中乙酸钠含量的快速测定

摘要

A rapid method for quantitative analysis of the content of sodium acetate in sodium diacetate by perchloric acid non-aqueous titration is studied.Dissolve the sample in glacial acetic acid and then add appropriate amount of acetic anhydride to improve the sensitivity of titration end-point.Use per-chloric acid standard solution titration until the color of solution changes from dark green to fruit green.The results show that the titration result of this method coincides with that of the national standard GB/T 25538-2010,the relative standard deviation ranges from 0.051% to 0.073%.This method provides easy operation and cheap instruments,and it is of good precision and accuracy.%建立了食品添加剂双乙酸钠中乙酸钠含量的快速测定方法。将样品直接溶解于冰乙酸中，根据样品中水分含量的大小加入适量的乙酸酐以提高滴定终点的灵敏性，使用高氯酸标准溶液滴定至溶液由暗绿色变为果绿色。实验结果表明：该方法滴定结果与国家标准中分析方法结果一致，方法的相对标准偏差(RSD)为0.051%~0.073%。该方法具有准确度高、精密度好、操作简单、实验仪器低廉的特点。