Multi-class method for veterinary drug residues in processed meat products by liquid chromatography coupled to orbitrap mass spectrometry: development and inter-laboratory validation

A multi-class method was developed for the determination of 72 veterinary drugs in meat-based foods. Samples were extracted using an acetonitrile/water mixture, followed by defatting and centrifugation. Analysis was performed by LC-HRMS/MS in positive electrospray ionisation mode. The method was validated in dry-cured ham in accordance with EU Regulation 2021/808, through an inter-laboratory study involving three laboratories. Quantification was based on matrix-matched calibration. For 54 analytes, recoveries were within 80%-120%, and inter-laboratory coefficients of variation (CVs) were below 25%. The applicability of the method to other processed Italian meat products, including lonzino, mortadella, and cooked ham, was evaluated. The method proved unsuitable for mortadella, likely due to its high fat content. A selection of commercial samples from local markets was also analysed to assess the occurrence of the target compounds, and no residues were detected in the 57 cured meat products.