Tailor it up! How we are rolling towards designing the functionality of emulsions in the mouth and gastrointestinal tract

There is a growing interest to design food emulsions with tailored digestibility-functionality during their journey in the oral cavity and gastrointestinal tract. In the present paper, we outline the current technology and provide some outlooks for future perspectives. Oil-in-water (O/W), water-in-oil-in-water (W/O/W), and water-in-water (W/W) emulsions confer several compartments to partition a wide array of biopolymers and small molecules for governing digestibility and triggering specific functionalities. Pickering stabilization of O/W emulsions enables to lower digestion and target enterocytes through decorating the particles with specific ligands. Moreover, the internal lipid phase can be structured to decline lipolysis. In W/O/W emulsions, the hydrophilic emulsifier type and oil viscosity determine the lipolysis and proteolysis extents/rates. Digestibility of biopolymers such as starch can be tuned using W/W emulsions. These latter emulsions also enable encapsulation of water-soluble vitamins and enzymes, and protection of probiotics in the stomach.