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Herein, we reported a facile method to fabricate ultra-stable, surfactant- and antimicrobial-free Pickering emulsions by designing and modulating emulsions' interfaces via zein/chitosan colloid particles (ZCCPs). Highly charged ZCCPs with neutral wettability were produced by a facile anti-solvent procedure. The ZCCPs were shown to be effective Pickering emulsifiers because the emulsions formed were highly resistant to coalescence over a 9-month storage period. The ZCCPs were adsorbed irreversibly at the interface during emulsification, forming a hybrid network framework in which zein particles were embedded within the chitosan network, yielding ultra-stable food-grade zein/chitosan colloid particles stabilized Pickering emulsions (ZCCPEs). Moreover, stable surfactant-free oil gels were obtained by a one-step freeze-drying process of the precursor ZCCPEs. This distinctive interfacial architecture accounted for the favourable physical performance, and potentially oxidative and microbial stability of the emulsions and/or oil gels. This work opens up a promising route via a food-grade Pickering emulsion-template approach to transform liquid oil into solid-like fats with zero trans-fat formation., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

We report for the first time the usage of mono-dispersed gliadin/chitosan hybrid particles as a particulate emulsifier for Pickering high internal phase emulsions (HIPEs) development. The hybrid particles with partial wettability were fabricated at pH 5.0 using a facile anti-solvent route. Stable Pickering HIPEs with internal phases of up to 83% can be prepared with low particle concentrations (0.5–2%). The hybrid latexes were effectively adsorbed and anchored at the oil–water interface to exert steric hindrance against coalescence. Concomitantly, the compressed droplets in Pickering HIPEs to form a percolating 3D-network framework endowed the emulsions viscoelastic and self-standing features. The protective effect of Pickering HIPEs on curcumin was confirmed, and the content of primary oxidation products in HIPEs was slightly lower than that in bulk oil. This work opens an attractive strategy to convert liquid oils to viscoelastic soft solids without artificial trans fats, as a potential alternative for PHOs. [ABSTRACT FROM AUTHOR]

Microstructure heterogeneity of emulsion films impaired their physical performances. This work attempted to fabricate novel high-barrier chitosan (CH) emulsion films by manipulating emulsion's interface architecture via Pickering stabilization approach. Some selected physical properties, including tensile property, water vapor permeability (WVP), and oxygen permeability (OP) as well as the microstructure of the films were evaluated. Film-forming emulsions (FFEs) based on zein/chitosan colloid particles-stabilized Pickering emulsions (ZCCPEs) were extremely stable, evidenced by the similar droplets size and size distribution in the FFEs and film matrix, endowing the films with homogeneous distributions of lipid droplets over their 3D network matrix. Interestingly, emulsion films exhibited excellent oxygen-barrier efficiency, and the OP of the films was decreased by 1−4 orders of magnitude when compared with CH films. This phenomenon may be associated with the novel interfacial architecture of ZCCPEs as well as film microstructure morphology based on ordered assembles of CH matrix and ZCCPEs. A schematic diagram for the formation pathway of ZCCPEs-loaded CH emulsion films was proposed to establish structure-function relationships of the films. This study opens a promising pathway for producing emulsion films with excellent oxygen-barrier capability via Pickering stabilization principle. [ABSTRACT FROM AUTHOR]

Metal organic frameworks (MOFs) have been considered to be robust adsorbent for the removing heavy metal ions from wastewater due to their unique properties such as large active sites, high specific surface area and high porosity, etc., however, their practical engineering application faces the problem of serious agglomeration. In this work, a new strategy of chitosan (CS) assisting MOF dispersion was proposed to develop the new generation of MOF-based adsorbents, namely, CS grafted UiO-66-NH 2 composite materials (CGUNCM). The UiO-66-NH 2 was selected and it was grafted onto the main chains of CS through covalent bonding interaction with the aid of glutaraldehyde, which was totally different from the common method that grafting molecular chains on the surface of MOFs resulting in the dramatic reduction of active adsorption sites. The results show that grafting MOFs onto CS main chains not only greatly improves the dispersion of MOFs but also reserves the morphology of MOFs as much as possible. The adsorption performances toward Cu(II) and Pb(II) were intensively studied by varying adsorbate concentration, ionic strength, the contact time, adsorption temperature and pH value of solution. The results show that the composite adsorbent exhibits high adsorption efficiency and the adsorption equilibrium can be reached within 45 min, and the maximum adsorption capacity toward Cu(II) and Pb(II) achieve 364.96 mg/g and 555.56 mg/g, respectively. Furthermore, the composite adsorbent shows good reusability. This work provides a new method of fabricating the MOF-based adsorbent and paves the way for the practical application of such adsorbents in wastewater treatment. [Display omitted] [ABSTRACT FROM AUTHOR]