Liquid chromatography coupled with Mass Spectrometry for multiple detection of hidden allergens in bakery-products: two case studies produced at pilot plant scale

Currently there is no cure for food allergies and having at disposal sensitive and accurate analytical methods to detect tiny amounts of multiple allergens in foods represents a crucial point for the protection of allergic consumers. Food processing represents a critical issue in the development of robust and reliable methods for allergen quantification due to the numerous and different chemical/structure modifications that could occur at protein level,1 often impairing detectability of the selected marker peptides. In this study, the reliability and the transferability of a LC-MS/MS method developed on a Triple Quadrupole mass spectrometer platform for multiple detection of traces of eggs, milk, soy, nuts, peanuts and sesame in highly processed food was investigated. In details, rusk was chosen as highly processed food since its production involves technological phases harder than those used for other bakey production and analysis were performed on advanced High Resolution Mass Spectrometer platform. In detail, the sensitivity of the method in terms of Limit of Detection (LOD) and Limit of Quantification (LOQ) along with a recovery estimation for each marker accomplished on samples enriched with each allergenic ingredient before processing at two different levels was performed. Moreover, the characteristics of the developed method were compared with the performance of a parallel method optimized by our group for detecting these six allergens in cookie matrix. This comparison also allowed to understand the applicability of these selected marker peptides to detect eggs, milk, soy, nuts, peanuts and sesame in bakery products produced at soft and harsh conditions, thus to be considered “universal” proteotypic peptides able to trace these culprit ingredients in bakery-foods despite the processing used for their production.