The role of conformational state of pH-shifted β-conglycinin on the oil/water interfacial properties and emulsifying capacities

This study investigated the influence of pH-shift treatment on the conformational state, interfacial properties and emulsifying capacities of β-conglycinin (7S proteins). The conformational state was evaluated using dynamic light scattering, intrinsic tryptophan fluorescence spectroscopy, and far-UV circular dichroism spectroscopy. The interfacial properties, including adsorption kinetics and dilatational viscoelasticity modulus were characterized at the oil/water interface. Emulsifying capacities and emulsion stability against thermal treatment (85 °C, 15min) were characterized by mean droplet size, flocculation index, adsorbed protein content, interfacial protein concentration and Zeta potential values. The results indicated that pH-shift treatment changed the conformational state and interfacial viscoelasticity of 7S proteins. The conformational changes of 7S proteins significantly affected their adsorption at the interface, improving the emulsion stability against thermal treatment.