Mass spectrometry-based proteomics methods for analysis of food allergens.

We review the features and the potential of advanced mass spectrometry (MS) in proteomic research together with applications in detecting and identifying for food allergens. Reliable, sensitive methods tracing ingredients of or relevant specific biomarkers for allergenic food are required to comply with food-labeling legislation. Food allergens are identified by proteolytic digestion upon isolating proteins (bottom-up approach) or directly analyzing intact proteins and their fragmentation products (top-down approach). Advanced separation methods are needed for a higher degree of resolution in order to separate complex mixtures of peptides. Food allergens can be characterized and identified by fingerprinting peptide masses or peptide fragments combined with computer search of databases. We also discuss development of mass analyzers, hybrid multi-stage instruments (e.g., Q-TOF, TOF2 and LTQ-FT-ICR), featuring other types of tandem MS (MS2) experiments.