Early film formation in protein-stabilised emulsions: Insights from a microfluidic approach

In conventional emulsification devices, interface formation and stabilisation occur within milliseconds. Protein network formation at liquid-liquid interfaces starts at time scales similar to those of droplet formation in conventional emulsification devices (i.e., in milliseconds). Classical methods, like drop tensiometry, do not allow measurements at these time scales. Using a tailor-made microchip, we probed droplet deformation to study the interfacial rheological properties of droplets, within time scales ranging from 0.16 to 1 s. We further investigated the coalescence stability of droplets at the same time scales. Whey protein isolate (WPI), pea protein isolate (PPI), or their blends were used as emulsifiers at 0.01–1 g/L. The rheological properties of the protein-interfaces showed that early network formation takes place (