High internal phase Pickering emulsions stabilized by submicron composite particles via ultrasound-assisted binding...

This study developed whey protein isolate-lysine (WPI/L) submicron composite particles via ultrasound-assistance for stabilizing high internal phase Pickering emulsions (HIPPEs). The results showed that composite particles prepared at 80 °C had a smaller particle size, higher surface hydrophobicity, and better emulsifying and foaming properties than those at 70 °C. The results of ultrasound treatment (600 W, 0, 5, 15, 30 min) revealed that WPI/L composite particles prepared at 30 min (80UWPI/L-30) possessed the highest random coil content, enhancing interfacial properties like equilibrium interfacial pressure, wettability and penetration rate, as well as the functional properties. HIPPEs prepared from optimized particles at different concentrations (2%, 3%, 4%) were assessed for physicochemical properties and stability. Emulsions stabilized by 4% 80UWPI/L-30 showed the smallest droplet size, highest absolute zeta potential, uniform microstructure, and remained stable for 14 d without phase separation, also resisting thermal stress due to a strengthened interfacial film with lysine.