Emulsions are formed when two immiscible liquids are mixed.
One liquid (the dispersed phase) is dispersed as droplets (from
0.10 lm to a few lm of diameter) in the other (the continuous
phase) (McClements, 2007). Forming emulsions requires energy
to increase the interfacial area between continuous and dispersed
phases. Emulsified systems are thermodynamically unstable
because of the surface tension between oil and water, which
opposes to the increase of interfacial area. Emulsions can be stabilized
by amphiphilic molecules, which adsorb in the oil–water
interface, decreasing the surface tension. They can also be stabilized
by solid particles which adsorb onto the interface between
the two phases and are called Pickering emulsions (Pickering,
1907). Besides, the stability of emulsions is conditioned by the
competition between attractive (Van der Waals, hydrophobic
interactions, electrostatic attractions, hydrogen bonds) and repulsive
forces (electrostatic repulsion, steric repulsion) between the
dispersed droplets