PROC-012: Protein-based Janus Particles formed by Electrohydrodynamic Process – An Application as Pickering Emulsifier

Pickering emulsions stabilized by Janus particles have gained interest due to their excellent stability. We propose a novel method to produce protein-based Janus particles using electrohydrodynamic co-jetting process. These Janus particles, composed of hydrophobic zein and hydrophilic sodium caseinate compartments, were characterized using scanning electron microscopy. The particle size, measured with zetasizer, was 600 nm for particles obtained in the supernatant after centrifugation whereas it was up to 8 µm for particles in a suspension of the precipitate. Janus particles were then emulsified with sago palm weevil (Rhynchophorus ferrugineus) larvae oil using a microfluidizer (9 kpsi and 3 passes) or ultrasonicator (15W at 2 intervals of 30s on and 60s off), resulting in stable 2 wt% oil-in-water Pickering emulsions. Emulsions stabilized with Janus particles (zein : sodium caseinate ratio of 4:1) at a concentration corresponding to 0.05 wt% protein in the final emulsion exhibited stability for 4 days, maintaining a consistent oil droplet size of 0.4 µm and 0.6 µm for microfluidizer and ultrasonicator methods, respectively. In conclusion, the electrohydrodynamic co-jetting process showed promise for efficient fabrication of Janus particles and both emulsifying methods demonstrated stable Pickering emulsions during storage.