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

摘要： 提出一种经典的质量分析法，进行乳制品中二氧化硅含量测定。结果表明：本方法最低检出限0．4g＆g，最低定量限为2．0g／kg，含量大于最低定量限时回收率介于91％～112％之间。该方法简单、快捷、有效，可用于乳制品中二氧化硅的测定。

关键词: 乳制品; 抗结剂; 二氧化硅; 测定