摘要
〔目的〕建立准确、简便、快速测定乳品中硝酸盐的方法。〔方法〕用电导检测—离子色谱法检测乳品中的硝酸盐。以碳酸钠—碳酸氢钠作淋洗液,在样品中先后加入醋酸和氢氧化钠溶液分别脱除蛋白质和脂肪等有机物,直接进样,以优化硝酸盐的离子色谱分离和测定条件。〔结果〕方法的检出限达0.015mg/kg,线性关系良好,本法测定了婴儿奶粉、孕产妇专用奶粉和鲜牛奶中的硝酸盐,加标回收率分别达94.6%,92.1%,109.6%。〔结论〕与国标法相比,本法灵敏度提高了100倍,方法简便易行,结果准确。
A simple and fast method was developed for the determination of nitrate in dairy products by ion chromatography with conductor detector. Taking Na2CO3-NaHCO3 as the eluent, CH3COOH and NaOH were added into the sample to remove protein and fat respectively. The requirements of separation and detection for nitrate ion were optimized. The detection limit of nitrate by this method was 0.015mg/kg. Calibration curves showed good linearity. The method has been used to analyze baby milk powder; milk power specialized for pregnant mothers and the fresh milk, respectively which the recoveries of standard addition are 94.6%, 92.1% and 109.6%. Compared with the method described in the China National Standard, the sensitivity is increased by a factor of 100 with simple operation and accurate result.
出处
《检验检疫科学》
2006年第2期30-32,共3页
Inspection and Quarantine Science
关键词
离子色谱法
硝酸盐
乳制品
牛奶
ion chromatography
nitrate
dairy products
milk
