Rapid Multidimensional Liquid-Gas Chromatography for the Analysis of Saturated Hydrocarbon Contamination in Foods Containing Vegetable Oil

This article describes a rapid heart-cutting liquid chromatography-gas chromatography (LC-GC) method for the analysis of mineral oil saturated hydrocarbons (MOSHs) found in a range of widely-consumed foods, including crisps, margarine, tinned tuna and vegetable oils. The automated LC-GC experiments were performed using a system equipped with a syringe-type interface capable of both heart-cutting and comprehensive two-dimensional analysis. The first dimension separation was achieved on a silica column operated under isocratic conditions using hexane. The heart-cuts were then transferred to a programmed temperature vaporizer. After the large volume injection (LVI), the target analytes were rapidly separated (similar to 9 min) using a micro-bore GC capillary column. The overall LC-GC run time enabled the analysis of around four samples in an hour. Various degrees of MOSH contamination ranging from "not detected" to around 390 mg/kg - were discovered in the thirty samples that were subjected to analysis.