Pickering food emulsions stabilized by bio-nanoparticle complexes: Super high internal phase and 3D printability

The use of high internal phase emulsion in renewable engineer functional food materials is challenging. Here, an edible sunflower oil-in-water high internal phase Pickering emulsion (HIPPE) was fabricated through complexation of oppositely charged cellulose nanofibrils (CNF) and nanochitin (NCh) as stabilizing agents. The CNF/NCh complexes can adsorb onto the surfaces of liquid droplets as well as their interfaces, which form a fortified protective stratum and an intricate three-dimensional network structure to prevent the fracturing and fusion of droplets. As a result, HIPPE can be kept at room temperature for at least 60 days, with a super high oil volume fraction of 88% (sunflower oil) and 89% (cyclohexane). In addition, due to the inherent microscale adjustability and viscoelasticity of HIPPEs, they can be used as edible emulgel inks and hierarchical porous structures for 3D printing via direct ink writing. This research will provide crucial insights and a platform for the future development and utilization of multifunctional emulsions in areas such as 3D foods and food-based superlight aerogels.