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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. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate for the first time the use of gliadin colloid particles (GCPs) as an effective particulate stabilizer of oil-in-water emulsions of natural oils and water. For this purpose, we fabricated GCPs through a facile anti-solvent precipitation procedure and demonstrated their uses in the formation of Pickering emulsions as well as Pickering high internal phase emulsions (HIPEs). We found that unmodified GCPs can produce stable, surfactant-free o/w emulsions with microscale droplet sizes under experimental mixing conditions at pH 4 and above. In contrast, the emulsions were not stable against coalescence at ∼pH 3.0. The microstructures, e.g., interfacial framework, GCPs partition between the continuous phase and interfacial region, and state of the droplets, of Pickering emulsions as a function of pH were visualized by optical microscopy and confocal laser scanning microscopy (CLSM), confirming that in addition to Pickering stabilization, the GCPs-based network and/or dispersed droplets-based network also contributed to the stabilization of the emulsions, in a pH-dependent manner. Clear correlations exist between colloid properties of the GCPs dispersions and the emulsion characteristics. Interestingly, stable surfactant-free Pickering HIPEs were fabricated by a facile shearing emulsification. This study opens a promising route based on Pickering HIPEs to transform liquid oils into viscoelastic emulsion gels with zero trans-fat and less saturated fat. The Pickering HIPEs possess promising potentials to replace solid fat in food formulations, which outline new directions for future fundamental research. [ABSTRACT FROM AUTHOR]