ION-EXCHANGER COLORIMETRY FOR MEASURING IRON (Ⅱ) IN POWDERED MILK FORTIFIED WITH IRON (Ⅱ) / 营养学报

A new spectrophotometric method, ion-exchanger colorimetry for measuring iron (Ⅱ) in powdered milk fortified with iron(Ⅱ) has been developed. The method was based on the direct measurement of the resin phase absorbance after the absorption of colored sample complex species. In this method, 1,10-phenanthroline was used as the colour reagent, citric acid-sodium citrate as buffer and citric acid-ammonia as masking agent.The recovery rate of the method was 102%. Coefficient of variation was 5.84%.This method was a sensitive, reliable and simple analytical method for the determination of iron (Ⅱ) in powdered milk fortified with iron (Ⅱ).It was also possible to determine iron(Ⅱ) in powder milk and other food.