Scouting for reliable allergen markers in complex food models produced at pilot scale in the ThRAll project

Rationale: In this communication, specific peptide markers tracing for milk, egg, peanut, soybean, hazelnut and almond contamination in complex food matrices were selected by mass spectrometry (MS). Methods: Discovery analysis by high-resolution MS was carried out on two incurred food matrices, chocolate bar and broth powder. Final spectra were processed via a commercial software for sequence identification. Results and conclusions: Candidate protein and peptide markers reporting for food contamination by six allergenic ingredients were identified by MS. The qualitative comparison of different conditions for extraction and purification provided preliminary information about best sample preparation protocol. Extraction by dual step approach including shaking and sonication in bath and purification by SEC/SPE turned out to be the most promising option for both incurred matrices. The results obtained with the chocolate bar provided an exhaustive list of potential markers for all six allergenic ingredients, whereas for the broth powder, a short-list of candidates was compiled due to the significant protein background from the matrix itself. The experimental identification of peptide markers was discussed and a final list of highly reliable candidates was selected for targeted method set up.