Fabrication of telechelic DNA bridged food emulsion gel as edible ink for 3D printing

Abstract Objectives Interdroplet interactions affect the properties and textures of emulsions. In this study, we creatively introduced telechelic DNA to link oil droplets directly at molecular scale to further improve the viscoelastic properties of emulsions. Materials and Methods A stable emulsion with 70% oil fraction was prepared by adding 40 mg/mL of whey protein isolate and peach gum polysaccharide complex (WPI–PGP complex). The addition of telechelic DNA (0.125–0.375 μmol/L) made the emulsion change from a cream-like state to a self-supporting gel. Results Rheological experiments confirmed that the telechelic DNA could improve the yield stress, storage modulus/loss modulus (Gʹ/Gʹʹ) and apparent viscosity of the emulsion gel in a concentration-dependent manner (0–0.375 μmol/L). Inverted fluorescence images clearly showed the interdroplet network of the emulsion gel linked by telechelic DNA. For 3D printing, the emulsion gel with a higher concentration (0.375 μmol/L) of telechelic DNA displayed better surface quality and dimensional resolution, indicating improved printability. Conclusion This study successfully designed a novel telechelic DNA-bridged emulsion gel, which showed great potential as edible ink for 3D printing.