Myofibrillar protein microgels stabilized high internal phase Pickering emulsions with heat-promoted stability

This study developed the myofibrillar protein microgel particles (MMP) stabilized high internal phase Pickering emulsions (HIPPEs) with heat-promoted stability. The effect of heat treatment intensity and the heat-promoted stabilization mechanism were investigated by analyzing the microstructure, rheology and interface properties of MMP stabilized HIPPEs. The storage modulus of emulsions displayed an increased trend during the heating up and then cooling down processes. The droplet size of HIPPEs gradually increased with increasing heat treatment intensity (60-121 °C for 5 or 30 min) and still remained stable after heat treatment above 100 °C for 30 min. The heat treatment resulted in the enhancement of the freeze-thaw and centrifugal stability of HIPPEs, implying a dominant contribution to the improvement of emulsion stability. The heat treatment promoted the hydrophobic interactions between MMP at the interface and the gradual formation of interface network structure. Then, it was also observed that a gradual increase in the interfacial expansion modulus (4.6–8.1 mN/m) and the formation of a high strength elastic film. This work provides a facile strategy to improve the stability of protein microgel stabilized HIPPEs, which is beneficial to the development of thermal processing emulsion-based foods.