OPTIMISATION OF PRESSURISED LIQUID EXTRACTION (PLE) FOR RAPID AND EFFICIENT DETERMINATION OF MINERAL OIL SATURATED HYDROCARBONS (MOSH) AND MINERAL OIL AROMATIC HYDROCARBONS (MOAH) IN CARDBOARD AND FOODS

Food can be contaminated from different sources with mineral oils that are composed of complex mixtures of saturated hydrocarbons (MOSH) and aromatic hydrocarbons (MOAH) the latter being of more concern to human health. Packaging can represent a primary source of food contamination especially when recycled cardboard or mineral oil based printing inks are used. Food grade mineral oils (largely used in the food industry) and environmental contamination are also important sources of contamination. Depending on the source of contamination, food processing and food composition, it can be difficult obtaining a complete MOSH and MOAH extraction by applying classic solvent extraction. Pressurised liquid extraction (PLE) is a powerful technique widely used for extraction of contaminants from environmental samples which can also be used in extraction from food. If traditional extraction methods using solvents at ambient temperature do not give good extraction efficiency, PLE can be used to give the required quantitative extraction yields using higher temperatures maintained under increased pressures. A PLE method for rapid and efficient MOSH and MOAH extraction from cardboard samples has been optimised in this research. Results obtained were compared to those obtained by applying the method developed by Lorenzini et al. [1]. The proposed method, involving extraction with hexane at 60 °C for 5 min, allows for processing of up to 6 samples in parallel with minimal sample manipulation and solvent consumption (about 6 mL per sample). The extract obtained can be directly analysed with on-line LC-GC [2] or processed with off-line SPE-GC [3]. PLE has also been investigated for use in MOSH and MOAH extraction from different food samples: when the method is optimised, it can replace slower traditional extraction methods obtaining higher extraction yields.