火焰原子吸收光谱法测定食用油脂中钠含量

FAAS Determination of Sodium in Edible Oil

摘要: 食用油脂样品经正己烷溶解,硝酸(1+99)溶液萃取,离心后取水相用火焰原子吸收光谱法测定其中钠离子的含量。钠离子的质量浓度在0.2~4.0 mg·L-1范围内与吸光度呈线性关系,检出限(3s)为0.004 7 mg·L-1。以橄榄油样品为基体,加入钠标准溶液按试验方法分析,测得回收率在72.4%~89.2%之间,测定值的相对标准偏差(n=6)在1.3%~2.8%之间。

Abstract: Samples of edible oil were dissolved with n-hexane and extracted with HNO3 (1+99) solution. After centrifugation, the content of Na+ ion in aqueous phase was determined by FAAS. Linear relationship between values of absorbance and mass concentration of Na+ ion was kept in the range of 0.2-4.0 mg·L-1, with detection limit (3s) of 0.004 7 mg·L-1. Recovery and precision of the method were tested by analyzing an olive oil sample with addition of sodium standard solution, giving values of recovery and RSD′s (n=6) in ranges of 72.4%-89.2% and 1.3%-2.8% respectively.