Behavior of protein aggregates via electrostatic interactions or hydrogen bonds during dough formation

The aggregation behavior of gluten proteins via electrostatic interactions or hydrogen bonds during dough formation was investigated. Proteins were extracted with 50 mM acetic acid or 4 M urea to break electrostatic interactions or hydrogen bonds, respectively. The extracted proteins were analyzed by size exclusion high performance liquid chromatography and two dimensional fluorescence difference gel electrophoresis. Acetic acid- and urea-soluble protein aggregates increased with dough development, indicating that electrostatic interactions and hydrogen bonds weakened during dough mixing. On the other hand, the some monomeric proteins (mainly α-gliadins) in dough aggregated via electrostatic interactions rather than hydrogen bonds. A model is proposed for gluten formation during dough mixing based on non-covalent bonds.