Proteomic Characterization of Wheat Protein Fractions Taken at Different Baking Conditions

Food processing conditionsaffect the structure, solubility, andtherefore accurate detection of gluten proteins. We investigated theinfluence of dough, bread, and pretzel making on the composition ofdifferent wheat protein fractions obtained by Osborne fractionation.The albumin/globulin, gliadin, and glutenin fractions from flour,dough, crispbread, bread, and pretzel were analyzed using RP-HPLC,SDS-PAGE, and untargeted nanoLC-MS/MS. This approach enabled an in-depthprofiling of the fractionated proteomes and related compositionalchanges to processing conditions (mixing, heat, and alkali treatment).Overall, heat treatment demonstrated the most pronounced effect. Label-freequantitation revealed significant changes in the relative abundancesof 82 proteins within the fractions of bread crumb and crust in comparisonto flour. Certain gluten proteins showed shifts or reductions in particularfractions, indicating their incorporation into the gluten networkthrough SS and non-SS cross-links. Other gluten proteins were enriched,suggesting their limited involvement in the gluten network formation.