气相色谱-氢火焰离子化检测器测定奶茶饮料中的胆固醇

Determination of chlolesterol in milk tea by GC-FID

目的:建立一种应用气相色谱仪-氢火焰离子化检测器测定奶茶饮料中胆固醇含量的快速检测方法。方法:样品中加入一定量无水硫酸钠,石油醚作为提取液,超声提取后,高速离心,利用气相色谱仪的毛细管色谱柱和氢火焰离子化检测器(FID)对上清液进行分离和检测。结果:利用该方法,胆固醇与杂质可以得到良好分离。在1.0～200.0μg/ml的线性范围内,相关系数大于0.999,最低检出量为1.5600 ng,当样品添加浓度为5.0～50.0 mg/kg时,方法回收率范围在88.89%～108.70%之间。结论:该方法操作简便,灵敏度高,重现性和选择性好,分离效果良好,最低检出量和回收率均符合微量分析的要求,是检测含脂肪食品中胆固醇的有效定性、定量方法。

Objective：To study a method for cholesterol determination in milk tea by gas chromatography -flame ionization detector（ GC -FID）. Methods：The cholesterol in milk tea was directly extracted by petroleum ether, and purified by anhydrous sodium sulfate and high speed centrifugation was developed, then detected by gas chromatography - flame ionization detector（ GC - FID）. Results：The detection limit of the method was 1. 5600 ng, the recoveries of 88.89% - 108. 70% when dopant concentration was from 5.0 mg/kg to 50.0 mg/kg, RSD was 6. 83 %. Conclusion：The method of determination of cholesterol in milk tea by GC - FID is low interference, easy to operated and accurate. It can be used in research of the cholesterol in liquid sample.