Design principles of oil‐in‐water emulsions with functionalized interfaces: Mixed, multilayer, and covalent complex structures

High internal phase Pickering emulsions stabilized by a cod protein-chitosan nanocomplex for astaxanthin delivery

High internal phase Pickering emulsions (HIPPEs) stabilized by a food protein have attracted widespread attention. In this study, a novel cod protein-chitosan nanocomplex was prepared through electrostatic interactions and used as a particle emulsifier to stabilize the oil-water interface. The application of the cod protein-chitosan nanocomplex was demonstrated in the formation of stable HIPPEs with an internal phase as high as 84%. The influence of the system composition on the stability, microstructure and rheology of the HIPPEs was determined. The HIPPEs stabilized by the cod protein-chitosan nanocomplex formed a compact three-dimensional network structure, which gave the emulsion a higher storage modulus, viscoelasticity and good thixotropy. Interestingly, the chemical stability of astaxanthin was significantly improved by the developed HIPPEs. The bioavailability of astaxanthin in the HIPPEs stabilized by the nanocomplexes of 2.0% (w/w) cod protein and 0.1% (w/w) chitosan reached 49%. In summary, these results demonstrated that the food-grade cod protein-chitosan nanocomplex had potential in the development of HIPPEs, which could be used as carriers for hydrophobic bioactive compound delivery.

The microstructure and physiochemical stability of Pickering emulsions stabilized by chitosan particles coating with sodium alginate: Influence of the ratio between chitosan and sodium alginate

The purpose of this study was to further improve the physiochemical stability of the chitosan (CS) particle-stabilized Pickering emulsion by coating with sodium alginate (SA). The effect of different mass ratios of CS and SA (1:0.5-1:2) on the microstructure, rheology and the stability of the emulsions were comprehensively evaluated by various methods such as optical microscope, scanning electron microscope, rheometer, and low-field nuclear magnetism. The multilayer emulsion with low content of SA (CS:SA = 1:0.5) presented bridging flocculation. If SA concentration was high (CS:SA = 1:1-1:2), the surface of the Pickering emulsion droplets was completely covered by the SA. At this time, multilayer emulsion droplets became stable due to strong electrostatic and/or steric repulsion. Too high SA concentration (CS:GA = 1:2) might also promote the accumulation of moisture. In addition, the CS/SA multilayer emulsion showed higher coalescence stability under different environmental treatments but its creaming stability and flocculation stability were still sensitive to pH (2, 4 and 10), temperature (4 °C and 80 °C) and ionic strength (300-500 mM). In all, the addition of the proper level SA (CS:GA = 1:1-1:2) could increase the stability of CS particle-stabilized Pickering emulsion.

Application of Advanced Emulsion Technology in the Food Industry: A Review and Critical Evaluation

The food industry is one of the major users of emulsion technology, as many food products exist in an emulsified form, including many dressings, sauces, spreads, dips, creams, and beverages. Recently, there has been an interest in improving the healthiness, sustainability, and safety of foods in an attempt to address some of the negative effects associated with the modern food supply, such as rising chronic diseases, environmental damage, and food safety concerns. Advanced emulsion technologies can be used to address many of these concerns. In this review article, recent studies on the development and utilization of these advanced technologies are critically assessed, including nanoemulsions, high internal phase emulsions (HIPEs), Pickering emulsions, multilayer emulsions, solid lipid nanoparticles (SLNs), multiple emulsions, and emulgels. A brief description of each type of emulsion is given, then their formation and properties are described, and finally their potential applications in the food industry are presented. Special emphasis is given to the utilization of these advanced technologies for the delivery of bioactive compounds.

Advances in edible nanoemulsions: Digestion, bioavailability, and potential toxicity

The design, fabrication, and application of edible nanoemulsions for the encapsulation and delivery of bioactive agents has been a highly active research field over the past decade or so. In particular, they have been widely used for the encapsulation and delivery of hydrophobic bioactive substances, such as hydrophobic drugs, lipids, vitamins, and phytochemicals. A great deal of progress has been made in creating stable edible nanoemulsions that can increase the stability and efficacy of these bioactive agents. This article highlights some of the most important recent advances within this area, including increasing the water-dispersibility of bioactives, protecting bioactives from chemical degradation during storage, increasing the bioavailability of bioactives after ingestion, and targeting the release of bioactives within the gastrointestinal tract. Moreover, it highlights progress that is being made in creating plant-based edible nanoemulsions. Finally, the potential toxicity of edible nanoemulsions is considered.