The Potential Application of Pickering Multiple Emulsions in Food

Abstract

Emulsions stabilized by adsorbed particles-Pickering particles (PPs) instead of surfactants and emulsifiers are called Pickering emulsions. Here, we review the possible uses of Pickering multiple emulsions (PMEs) in the food industry. Food-grade PMEs are very complex systems with high potential for application in food technology. They can be prepared by traditional two-step emulsification processes but also using complex techniques, e.g., microfluidic devices. Compared to those stabilized with an emulsifier, PMEs provide more benefits such as lower susceptibility to coalescence, possible encapsulation of functional compounds in PMEs or even PPs with controlled release, etc. Additionally, the PPs can be made from food-grade by-products. Naturally, w/o/w emulsions in the Pickering form can also provide benefits such as fat reduction by partial replacement of fat phase with internal water phase and encapsulation of sensitive compounds in the internal water phase. A possible advanced type of PMEs may be stabilized by Janus particles, which can change their physicochemical properties and control properties of the whole emulsion systems. These emulsions have big potential as biosensors. In this paper, recent advances in the application of PPs in food emulsions are highlighted with emphasis on the potential application in food-grade PMEs.

Keywords: Janus emulsion; Janus particles; Pickering multiple emulsions; Pickering particles; food-grade.

Figure 1

Examples of Pickering particles behavior on water–oil interface, determined by the wettability of solid particles.

Figure 2

w/o/w and o/w/o PMEs with both interfaces stabilized by PPs (for simple and multiple emulsions).

Figure 3

Schematic representation of possible PME preparations.

Figure 4

The scheme of the required behavior of w/o/w PMEs in gastrointestinal tract.