Multi-Target Detection of Nuts and Peanuts as Hidden Allergens in Bakery Products through Bottom-Up Proteomics and High-Resolution Mass Spectrometry

Abstract

Due to the growing global incidence of allergy to nuts and peanuts, the need for better protection of consumers sensitive to those products is constantly increasing. The best strategy to defend them against adverse immunological reactions still remains the total removal of those products from their diet. However, nuts and peanuts traces can also be hidden in other food products, especially processed ones, such as bakery products, because of cross-contamination occurring during production. Precautionary labelling is often adopted by producers to warn allergic consumers, usually without any evaluation of the actual risk, which would require a careful quantification of nuts/peanuts traces. In this paper, the development of a multi-target method based on liquid chromatography-tandem high resolution mass spectrometry (LC-MS, MS/MS), able to detect traces of five nuts species (almonds, hazelnuts, walnuts, cashews and pistachios) and of peanuts in an in-house incurred bakery product (cookie) through a single analysis is described. Specifically, allergenic proteins of the six ingredients were used as the analytical targets, and the LC-MS responses of selected peptides resulting from their tryptic digestion, after extraction from the bakery product matrix, were exploited for quantification, following a bottom-up approach typical of proteomics. As a result, nuts/peanuts could be detected/quantified down to mg·kg−1 levels in the model cookie, thus opening interesting perspectives for the quantification of hidden nuts/peanuts in bakery products and, consequently, for a more rational use of precautionary labelling.

Microfluidic Chip Coupled with MALDI-TOF MS for Multitarget Detection of Allergens in Crucian Carp (Carassius auratus)

“…8 Luparelli et al developed a multitarget method based on liquid chromatography−tandem high resolution mass spectrometry to detect traces of five nut species (almonds, hazelnuts, walnuts, cashews, and pistachios) and of peanuts in an in-house− incurred bakery product (cookie) through a single analysis. 9 Allergen-specific antibodies play a major role in the development, maintenance, and treatment of allergic diseases. 10 Antibodies can be monoclonal or polyclonal, depending on their ability to bind one or more than one epitope.…”

“…Filep et al developed a fluorescent multiplex array for the simultaneous quantification of food allergens using specific allergenic proteins from peanut, tree nut, cow’s milk, egg, soy, fish, shellfish, sesame, mustard, and celery . Luparelli et al developed a multitarget method based on liquid chromatography–tandem high resolution mass spectrometry to detect traces of five nut species (almonds, hazelnuts, walnuts, cashews, and pistachios) and of peanuts in an in-house–incurred bakery product (cookie) through a single analysis …”

Food allergen analysis: A review of current gaps and the potential to fill them by matrix‐assisted laser desorption/ionization

“…Studies applying LC–MS/MS to the analysis of food allergens have proliferated and include: on seven allergens in flour and bread (Heick et al., 2011), cow's milk protein in cookies (Cordeiro et al., 2021), on coconut protein (Piredda et al., 2022), milk in meat‐based foods (Bianco et al., 2022), caprine and bovine milk allergens (Nelis et al., 2023), flaxseed storage proteins (Bueno‐Díaz et al., 2022), ovalbumin (Röder et al., 2021), egg milk and peanut in foods (Xiong et al., 2021), egg and milk in samples (labelled no milk and egg) (Fan et al., 2023), nuts and peanuts hidden in bakery products (Luparelli et al., 2023), piscine gelatine (Grundy et al., 2023), crustacean tropomyosin and arginine kinase in food matrix (Li et al., 2022), and multiallergens in chocolate (Henrottin et al., 2023). The publication of the AOAC First action 2017.17, “Detection and quantitation of selected food allergens by LC‐MS/MS” (New et al., 2020) and of BS EN 17644:2022 “Foodstuffs‐Detection of food allergens by liquid chromatography‐ mass spectrometry (LC‐MS) methods—General considerations” (European Committee for Standardization, 2022) has aided comparable robust, rugged (Burns et al., 2009), and reproducible results to be obtained by different analysts, instrumentation, and laboratories.…”