Carboxylated chitin nanowhiskers enhanced stabilization of Pickering and high internal phase Pickering emulsions

Pickering emulsions stabilized by the emulsifiers derived from biobased materials have been widely used in food related fields. In the current study, Pickering emulsions possessing internal phase volume fractions (ɸ) from 0.5 to 0.8 were successfully prepared by mechanical emulsification methods using carboxylated chitin nanowhiskers (C-ChNWs) as the emulsifiers. C-ChNWs suspensions obtained by ammonium persulfate (APS) oxidation showed high stability and possessed a Zeta potential of −48.9 mV. FTIR and XRD analyses indicated the α-chitin crystal structure could be maintained following APS oxidation. The C-ChNWs could form a three-dimensional network structure at the interface and endow the emulsion with high stability and viscoelastic features. Morphology results demonstrated these were oil-in-water emulsions. Moreover, the prepared high internal phase Pickering emulsions (HIPPEs; ɸ >0.74) showed good texture characteristics for high-resolution 3D printing. This work further validated the potential of nanochitin derived from biomass as an outstanding Pickering emulsion stabilizer.