Pickering Emulsions as Catalytic Systems in Food Applications

Abstract

Enzyme catalysis is important in food processing, such as in baking, dairy, and fiber processing and beverages. A recent advancement in catalysis is the development of Pickering emulsions as enzymatic catalytic systems; however, the use of Pickering emulsions (PEs) as catalytic systems in foods remains largely underdeveloped. Challenges exist that inhibit the widespread adoption of PEs as catalytic systems in foods. These limitations include the limited food-grade solid particle stabilizers, their poor dual wettability, and the potential effects of surface modifications of the solid particles on the stability and efficiency of the PEs. In this Review, the two types of PE catalysis (Pickering-assisted catalysis and Pickering interfacial catalysis), their formation, and some of their applications in the food industry are presented. In addition, the proposed solutions and strategies to improve the PE catalyst design are introduced. An outlook on how the field of PE catalysis will progress is briefly highlighted.

Figure 1

Schematic diagram of water-in-oil Pickering emulsions with (A) Pickering-assisted catalysis, (B) Pickering interfacial catalysis, and (C) Pickering-assisted interfacial catalysis. C = Catalyst. N = Nanoparticle.

Figure 2

Formation of phytosterol esters from phytosterol and fatty acid facilitated by the Pickering emulsion catalyst.

Figure 3

Schematic diagram of a lipase-nanotube-stabilized reaction to transform triacylgerols into fatty acids.