Emulsions and suspensions are systems formed by at least two phases; one of
them dispersed into another. For their preparation these generally unstable structures
require the addition of extra molecules that improve either their thermodynamic or kinetic
stability. Traditionally small amphiphilic molecules have been used for this purpose. More
recently, the surface and rheologic properties of biopolymers have been modified in order
to “tune” their properties as to improve emulsions and suspensions stability.
Most of the research and technological developments related to emulsions performed so
far imply water as one of the involved phases. Non-aqueous, oil-in-oil, anhydrous or
waterless emulsions, are common names for the dispersed systems in which water is
absent. Even though the first reports in this subject were published around 50 years ago
the literature on this area is sparse. In the recent years, non-aqueous emulsions became
attractive as potential vehicles for the development of drug delivery systems and
healthier foods. This led to the design of novel and simpler methods for the dissolution
of polymeric surfactants into edible vegetable oils and improved dispersion of nonaqueous
phases into structured oils giving a result very stable non-aqueous emulsion
with tunable rheological properties. These emulsions have potential applicability to
improve nutritional qualities of foods as well as to design vehicles for hydrophobic
active pharmaceutical ingredients.
In this chapter, we will summarize the recent advances in the basic principles involved
in biopolymer stabilization of non-aqueous emulsions and their potential applications
for the design of foods and medicines with improved performance.
Keywords: Biopolymers, emulsifier, ethylcellulose, graft copolymers, inulin,
kinetic stability, non-aqueous emulsions, rheology, thermodynamic stability,
viscosity.