气相-离子迁移质谱在植物油种类识别中的应用

Application of GC-IMS in variety discrimination of edible vegetable oils

在3因素3水平的正交试验设计优化气相-离子迁移谱(gas chromatography-ion mobility spectroscopy,GC-IMS)检测系统参数的基础上,通过采用顶空萃取的方式,使用GC-IMS联用分析技术获取了5种植物油和芝麻油不同加工工艺的特征挥发性有机物(volatile organic compound,VOCs)的GC-IMS指纹离子迁移谱,分析了气相(gas chromatography,GC)保留时间-离子迁移谱(ion mobility spectroscopy,IMS)漂移时间的三维信息,得出了通过GC-IMS三维信息上的出峰时间、数量和峰强度等信息的差异,可以实现植物油的种类的准确识别以及加工工艺改变与VOCs变化的规律的结论,结果证明,GC-IMS分析技术在植物油的品种识别、加工工艺识别、原产地识别和纯度检测等方面有着广阔的应用前景。

Through three-factor three-level orthogonal experiment,parameters for gas chromatography-ion mobility spectroscopy( GC-IMS) detection were optimized and headspace extraction was employed to obtain GC-IMS fingerprint spectra generated by characteristic volatile components( VOCs) of five common edible vegetable oils and sesame oils prepared under different processing parameters. GC-IMS assay displayed peak difference of each vegetable oil in three-dimensional information at retention time in gas phase and at ion mobility rate in IMS. It is concluded that accurate discrimination on edible vegetable oils of different varieties and from different processing techniques can be realized through analyzing peak appearance time,peak number and peak intensity of their GC-IMS three-dimensional information. This study demonstrates that GC-IMS analytical technology has broad applicative perspective in discriminating variety,processing technique,origin,purity and other features of edible vegetable oils.