Mineral Oil: A Complete Hardware and Software Solution for Qualitative & Quantitative Analysis Using GC×GC-TOFMS/FID

Mineral oil hydrocarbons (MOHs) are complex mixtures deriving from crude oil. They consist of two main fractions, namely mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH). The analysis of MOHs in food is a challenging task, due to the high complexity of the matrices and the high affinity of mineral oil towards the lipid fraction and/or other interfering components (e.g., carotenoids, terpenoids, olefins). The method of election for the quantitative determination of MOHs is LC-GC-FID. The resulting chromatograms are typically containing “humps”, also known as unresolved complex mixtures (UCM). In many cases, UCM is very difficult to interpret as the FID is a non-selective detector, and additional confirmatory methods are needed. In this respect, GC×GC-ToFMS is a well-established solution to characterize the MOSH and MOAH fractions in detail revealing the presence of markers of contamination (e.g., hopanes, dibenzothiophenes, diisopropylnaphthalenes POSH, PAO, etc.) as well as natural interferences (e.g., terpenoids). In addition, the GC×GC-ToFMS contour plots provide highly detailed qualitative information on the characterization of MOSH and MOAH fractions answering, as an example, the request of the EFSA and the European Union to characterize more in detail the 3-7 ring MOAH fractions. Recently, a full solution, including all hardware and software tools, was developed and validated, enabling automatic processing of quantitative data (GCxGC-FID), thanks to the use of a novel software algorithm developed to integrate 2D humps. We are able to demonstrate full qualitative and quantitative results for a range of challenging food sample matrices, such as palm oil and coconut oil.