Poster de Florence Lacoste, Responsable Département Analyse et Expertise à l’ITERG, 14th Euro Fed Lipid Congress, Ghent, Belgique, 18-21 septembre 2016
An interlaboratory study was conducted in 2015 to evaluate a method for determining mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) in vegetable oils and fats and foodstuff on basis of vegetable oils.
The fraction of MOSH and MOAH are isolated and separated by an HPLC-GC-FID system. MOSH and MOAH fractions are separated on a silica gel column using a hexane-dichloromethane gradient and each transferred to GC while triglycerides are kept on the HPLC column. MOSH and MOAH are quantitated by internal standard added before analysis. Verification standards are added monitoring proper HPLC fractionation and GC transfer conditions.
A set of 8 oil samples and 2 food samples delivered in double blind were assayed by 12 collaborating laboratories from three European countries. Sample matrices included virgin olive oil, refined olive pomace oil, refined sunflower oil, crude soybean oil, palm oil, margarine and mayonnaise ranging from 4 mg/kg to 197 mg/kg for MOSH, and from 2 mg/kg to 51 mg/kg for MOAH. Reproducibility (RSDR) ranged from 8.7 % to 22.7 % for samples containing more than 10 mg/kg of MOSH. Reproducibility (RSDR) ranged from 17.0 % to 51.4 % for samples containing more than 10 mg/kg of MOAH. Based on the precision data, the limit of application of the method was fixed at 10 mg/kg for both MOSH and MOAH with the method as described.
The author would like to thank the following collaborators for their participation : Ludger Brühl, Max Rubner-Institut (MRI), Germany. Monika Mainka, SGS Institut Fresenius GmbH, Germany. Eileen Schulz, Institut Kirchhoff Berlin GmbH, Germany. Lilli Reinhold, LAVES LVI BS/H, Germany. Franziska Janusch, Eurofins WEJ Contaminants GmbH, Germany. Thomas Funke, Chemisches und Veterinäruntersuchungsamt Münsterland-Emscher-Lippe, Germany. Silke Horst, LUA Dresden, Germany. Sabrina Moret, University of Udine, Italy. Emiliano Castellano, Silliker Italia S.p.A, Italy. Martin Rijkee, Handelslaboratorium Dr. A. Verwey, the Netherlands. Maurus Biedermann, Kantonales Labor Zürich, Switzerland. Thomas Baumgartner, COOP, Switzerland.
This work was financed by the European Commission within the standardization mandate M/463 in the field of methods of analysis for food contaminants. It was also financially supported by Terres Univia.