Abstract
Three-dimensional (3D) bioprinting of emulsion gels is expected to achieve a flexible design of dysphagia diets for individuals with difficulty in swallowing. In this study, the 3D bioprinting of emulsion gels have been achieved using radiofrequency (RF) and microwaves (MW). The textural properties were controlled using different RF and MW frequencies. The structure of an emulsion gel ink was composed of ovalbumin, xanthan gum, MgCl(2), Tween 80, and canola oil, satisfying the dysphagia diet criteria. The RF treatment at 200 MHz effectively improved the hardness of the emulsion gel by forming thick fibrous aggregates of ovalbumin and ovotransferrin. A 3D-bioprinting system equipped with LEGO Mindstorm EV3 and RF/MW heating was developed in this study to prepare structured emulsion gels. The properties of the 3D-printed gels were found to be equivalent to those of the gels obtained by batch RF/MW heating, satisfying the standards of textural properties for dysphagia diets. The developed RF/MW 3D-bioprinting of hydrogels can be further applied to products such as artificial or cultured meats. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1038/s41598-025-06804-1.