气相色谱-质谱法测定打蜡脐橙的石蜡含量

Determination of paraffin added into oranges by gas chromatography-mass spectrometer methods

中文关键词:  脐橙  石蜡  气相色谱-质谱法  果蜡

英文关键词:oranges  paraffin  GC-MS method  fruit wax

中文摘要:

      目的 建立气相色谱-质谱法检测打蜡脐橙中掺杂石蜡的分析方法。方法 脐橙果皮样品经正己烷提取、旋转蒸发浓缩后, 加入1 mL的浓硫酸进行净化, 所得正己烷提取液过0.22 μm膜后进气相色谱-质谱分离检测。结果 通过对样品中正二十四烷、正二十六烷、正二十八烷、正三十烷4种主要正构烷烃的测定, 可以定性地鉴别是否掺杂石蜡。4 种正构烷烃在0.5~100 mg/kg浓度范围内呈良好的线性关系, 线性回归系数r均大于0.9984。该方法定量限为10 mg/kg, 平均回收率为82.4%~102.4%, 相对标准偏差(RSD)1.6%~7.3% (n=6)。结论 该方法简便、稳定、适用性强, 可用于打蜡脐橙中是否含有石蜡的准确判定。

英文摘要:

      Objective To establish a method for the determination of the illegally-added paraffin in oranges by gas chromatography-mass spectrometer (GC-MS). Methods The samples were extracted with hexane and purified by 1 mL of sulfuric acid, and the analytes were passed through 0.22 μm membrane filter and chromatographically analyzed by GC-MS. Results Whether the paraffin was adulterated could be quali-tatively identified via the 4 n-alkanes. The correlation coefficients were all more than 0.9984. The limits of quantification were 10 mg/kg. The recoveries were 82.4 %~102.4 % and the relative standard deviations were 1.6%~7.3% (n=6). Conclusion The established method is simple, reliable, and applicable for the accurate determination of paraffin in oranges.