Membrane Emulsification for Encapsulation of Bioactives: Application to the Encapsulation of Antioxidants

Abstract

Membrane emulsification (ME) is an alternative to classical emulsification processes with several advantages such as low energy requirement and low pressure and shear stress applied. ME is an interesting technique to encapsulate sensitive actives like antioxidants. In this chapter, we first review the main principles of ME by focusing on two main configurations: direct membrane emulsification (DME) and premix membrane emulsification (PME), and the effect of several parameters, which control the emulsion droplet size and transmembrane flux. Some parameters are related to the process (shear rate, pressure, pore size, membrane material, and number of cycles in case of PME) and some other are associated to the formulation (dispersed phase content, surfactants, and viscosity of both phases). Finally, the application of ME in encapsulation of antioxidants through oil-in-water (O/W), water-in-oil (W/O) emulsions and water-in-oil-in-water (O/W/O) double emulsions and other colloidal systems is discussed. Overall, ME is an alternative method for encapsulation of antioxidants components, with advantages (control of droplet size, low droplet size distribution, low pressure and shear rate applied) and drawbacks (membrane fouling, especially with protein surfactants).