Validation of the liquid chromatography-comprehensive multidimensional gas chromatography-time-of-flight mass spectrometer/flame ionization detector platform for mineral oil analysis exploiting interlaboratory comparison data

Mineral oils, classified into two main fractions, namely saturated (MOSH) and aromatic hydrocarbons (MOAH), originate from petroleum. Their determination in food is challenging due to the difficulty of isolating them from the matrix and the presence of natural interferences, leading to low reproducibility of the results among different laboratories. Therefore, standardized procedures are highly required to minimize the uncertainty caused by various sources (e.g., integration, interference removal, etc.). However, at present, a few sample preparation procedures have been standardized, while the analytical determination is mainly performed using the hyphenated liquid-gas chromatographic technique coupled with a flame ionization detector (LC-GC-FID). However, LC-GC-FID is still not enough for confirmatory purposes, for which the use of comprehensive 2D GC (GC × GC) has been suggested. Recently, the use of a fully integrated platform for routine and confirmatory purposes has been proposed by Bauwens and co-workers (2022), namely LC-GC × GC-time-of-flight mass spectrometer (ToFMS)/FID. The aim of this work is to validate the quantification of MOSH and MOAH performed by LC-GC × GC-FID supported by the use of a recently developed integration software. The validation was performed by taking advantage of the participation in several recently organized interlaboratory comparisons organized by the Joint Research Center (to harmonize and validate the method for the determination of MOAH in infant formula products) and by the German Society for Fat Science and the French Technical Institute for the Study and Research of Fats (to improve the standardized European method for MOSH and MOAH in fats, i.e. EN 16995:2017). Data obtained by using LC-GC × GC-FID were in good agreement with those from the ILCs, in terms of recovery, precision, accuracy, and repeatability.