Determination of Iodine Content in Saudi Milk Products

Abstract

 Low level concentration of iodine was determined in various milk products for adult and baby milk powders by Inductively Coupled Plasma Mass Spectrometry (ICP-MS) method. It is a reliable method for the determination of iodine in milk samples, using alkaline digestion with potassium hydroxide KOH solution in an oven. After digestion, a stabilizer is added and the solution is taken to volume, then filtered and analysed by ICP-MS either directly or after dilution. Samples for investigation were collected from domestic market. The detection limits of current Iodine not affected by interfering from milk gradient, the minimum detection limit (MDL) of Iodine approaches 10 ppb was achieved. This method showed excellent results for aqueous iodide solutions, although the complex milk digest matrix made the method unsuitable for such samples. So, investigation of the iodine species is achieved through the oxidation and extraction of iodine milk samples, the digestion was carried out to control the iodine chemistry. Iodine concentrations were ranged of 0.17 – 5.1 mg/kg for various samples, the accuracy of the method ranged from 95 to 100%.