氮吹-气相色谱法测定植物油BHA与BHT

Determination of BHA and BHT in Vegetable Oil by Gas Chromatography for Nitrogen-purge

目的探讨气相色谱法检测食用油脂中BHA、BHT样品的前处理法。方法在相同检测条件下比较柱层析后氮吹和减压浓缩2种样品前处理方法的结果。色谱条件为:色谱柱为长2.0 m内径3 mm不锈钢柱,内装涂有10%QF-1(m/m)的Gas chrom Q(80～100目)担体。气化室温度200℃,检测室温度200℃,柱温140℃。结果 2种前处理方法的相对标准差均小于5%,回收率在88.7%～96.2%之间,RSD为2.70%～3.78%,检出限为0.004 g/kg。结论 2种前处理方法测定结果差异无统计学意义,氮吹-气相色谱法简便、准确、重现性好,可用于植物油中BHA、BHT的测定。

Objective To explore the pretreatment technique for the detection of BHA and BHT from edible oils and fats by using gas chromatography.MethodsComparing the test results of two extraction and purification methods of nitrogen-purge and vacuum concentration by gas chromatography in the same test conditions of GC.The chromatographic conditions were suggested as follows：Gas chrom Q（80100mesh）covered by10%QF-1（m/m）in 2.0×3 mm stainless steel column was used as stationary phase,injection temperature 200 ℃,detector temperature 200 ℃,column temperature 140 ℃.ResultsThe RSDs of two pretreatment technique were all lower than 5%,the recovery rate was 88.7%-96.2%and the detection limit were 0.004 g/Kg.ConclusionIt showed no statistical difference between two pretreatment methods of nitrogen-purge and vacuum concentration.The gas chromatography of nitrogen-purge is simple and accurate,and has a good reproducibility for the determination of BHA and BHT from vegetable oil.