Emulsifying and Surface Properties of Wheat Gluten under Acidic Conditions

The solubility of wheat gluten was greatly improved at pH 4 or lower where it showed good emuisifying activity. This might be due to its high surface activity in the acidic pH range and the formation of a stable protein film surrounding the oil droplets. Among the major gluten proteins, gliadins showed higher surface activity than glutenins. The content of glutenins in the adsorbed protein film was higher than that of gliadins, and glutenins are likely to have been adsorbed more tightly than gliadins. These results suggest that gluten proteins exhibit complex behavior, such as adsorption/desorption/displacement/rearrangement during the adsorption process in a gluten-stabilized emulsion. La solubilite du gluten de ble augmente a pH 4. C'est un bon emulsifiant a pH acide, grâce a ses proprietes de surface et a la formation d'un film proteique stable autour des gouttelettes lipidiques. Les gliadines ont de meilleures proprietes superficielles que les glutenines. Les glutenines sont plus facilement adsorbees au niveau du film proteique. Au niveau d'une emulsion stabilisee par le gluten, les proteines ont une activite complexe d' adsorption, desorption, deplacement et rearrangement au cours de la phase d'adsorption.