Edible jammed deep eutectic solvent-in-oil emulsions for 3D food printing

Concentrated emulsions, when their volume fractions exceed a critical value, tend to adopt a jammed structure and exhibit solid-like behavior. In this work, we develop a novel, edible high internal phase emulsion that incorporates an edible deep eutectic solvent (DES) as the dispersed phase, along with sunflower oil and Span 80 as the continuous phase, to formulate DES-in-oil emulsions. The rheological properties of the resulting DES-in-oil emulsions are thoroughly examined, focusing on the yield stress and storage modulus, which are indicative of solid-like characteristics. Additionally, the emulsion's microstructure is analyzed using optical microscopy to determine the size distribution of the DES droplets. Our study further explores the impact of agitation time on the emulsion's formation, revealing that prolonged agitation strengthens the emulsion's mechanical properties by reducing droplet sizes. This innovative emulsion showcases potential applications in 3D food printing, where it can be used to directly form predefined solid structures. Such printed food can assume various shapes without requiring post-processing, maintaining shape integrity and self-sustainability for up to four months.