奶粉中Ca、Fe、Zn三种微量元素的测定

Study on the Determination of the Calcium,Iron and Zinc in the Milk Powder

目的〕建立奶粉中Ca、Fe、Zn样品的前处理和火焰原子吸收检测方法。〔方法〕奶粉中的Ca、Fe、Zn经三种样品前处理方法处理 :湿式消解法、干法灰化法和微波消解法后 ,用火焰原子吸收测定。〔结果〕选择了最佳酸度范围和测定条件 ,定量测出了Ca、Fe、Zn的含量。Fe、Zn的最佳酸度范围为 4 %左右。三种方法的相对标准差RSD %均在 0 .0 2～ 2 .0 0 ,加标回收率在 93.7%～10 4 .2 6 %。〔结沦〕三种样品前处理方法的灵敏度、精密度都较高 ,准确率好 ,适用于奶粉Ca、Fe、Zn的分析测定。

(Objective〕Building the preliminary finish of calcium,iron and zinc samples and detecting method of flame atomic absorption in the milk powder.〔Method〕The calcium,iron and zinc in the milk powder were handled by three preliminary finish methods:wet slacking,dry cineration and microwave slacking,then they were detected by the flame atomic absorption.〔Result〕Through selecting the best acidity range and detecting condition,the calcium,iron and zinc constitution were quantitatively determined.The best acidity range was 4 percent or so.The relative standard deviations(RSD%) of the three methods were all from 0.02 to 2.00.The recovery rate were from 93.7% to 104.26%.〔Conclusion〕The sensitiveness and precision of the preliminary finish methods of the three samples were so high and the accuracy was so good that it was fit for the determination of the calcium,iron and zinc in the milk powder.