Bibliographical study of water-in-water emulsions and their stabilization

Abstract

The interactions of water-soluble biopolymers can cause the separation of hydrophilic phases and the dispersion of one phase in the other resulting in water-in-water emulsions. These water-in-water emulsions can have different applications in food because they allow traditional textures without the need to use unhealthy ingredients such as fats. Water-in-water emulsions, unlike oil-water emulsions, cannot be stabilized by surfactants, which means that one of the biggest impediments in the use of water-in-water emulsions is their stabilization. Recently studies have determined that these emulsions can be stabilized from the addition of particles which are located at the interface of the two aqueous phases preventing a macroscopic separation of phases. The addition of particles in oil-water emulsions has been widely studied for years in contrast to water-in-water emulsions. The behaviour of water-in-water emulsions stabilized by the addition of particles is quite different from that of oil-water emulsions because the interfacial tension is much lower and the much larger length scale at which the interphase expresses itself. This work deals with a bibliographic review of different water-in-water emulsion stabilization studies giving importance to emulsions with possible future applications in food and the factors on which this stabilization depends.