关键词: 乳制品; 抗结剂; 二氧化硅; 测定

Abstract: A method was proposed to determine silica dioxide, an anti-caking agent, in milk powder. After high temperature ashing, samples were dissolved in acid to remove soluble salts and other substances. The precipitate (silica dioxide and insoluble solids) was burned at a high temperature to a constant weight and treated with hydrofluoric acid to remove silica dioxide. Finally, the remaining residue was collected and burned again to a constant weight. As a result, this weight loss was silica dioxide. The limit of detection and limit of quantification of this method were 0.4 g/kg and 2.0 g/kg, respectively. Average recovery rates of silica dioxide in spiked blank samples ranged from 91% to 112%. This method was simple, rapid effective, and applicable for the determination of silica dioxide in milk powder.

Key words: milk powder；anti-caking agent；silica dioxide