To　understand　the　role　of　native　aggregation　state　(NAS)　of　soluble　wheat　gluten　and　fractions　during　deamidation　in　a　carboxylic　acid/heat　water　solution,　changes　in　conformation　and　deamidation　behavior　as　function　of　protein　concentration　from　dilute　to　semi-concentrated　regimes　to　control　NAS　were　investigated　by　physicochemical　properties,　SDS-PAGE,　molecular　force　change,　intrinsic　fluorescence　emission　spectroscopy　(IFES)　and　FTIR.　Our　data　show　that,　in　this　solution,　the　deamidated　proteins　displayed　features　characteristic　of　more　scattered　and　flexible　polymer　structure　in　dilute　concentration　than　concentrated　ones.　Degree　of　deamidation　(DD),　HD　and　Zeta　potential　exhibited　strongly　oppositely　with　the　decreasing　concentration.　HWM-GS,　omega-gliadins　and　LWM-GS　degraded　into　smaller　peptides　with　decreasing　of　NAS.　FTIR　and　IFES　displayed　that　improved　molecular　flexibility　with　decreasing　of　concentration　as　detected　by　the　increasing　content　of　beta-turn　and　I3-sheet,　as　well　as　the　red-shift　of　wheat　gluten　and　gliadins　at　the　expense　of　alpha-helix.　Hydrophobic　and　hydrogen　bond　increased　gradually　and　were　dominant　in　inter-molecule　as　function　of　increasing　concentration.　The　above　information　demonstrated　that　NAS　of　soluble　wheat　gluten　dominated　changes　of　deamidation　behavior　and　conformation　in　a　carboxylic　acid/heat　water　solution.　(C)　2016　Elsevier　Ltd.　All　rights　reserved.