Callus-based 3D printing for food exemplified with carrot tissues and its potential for innovative food production

This paper proposes a novel approach to implement a plant cell-laden hydrogel model that could extend the application range of plant-based food production to unique food texture. Callus based food-inks were prepared by blending a callus dispersion with 4% alginate at ratios of 1:2, 1:1, and 2:1 (w/w). During the 3D food printing process, all samples were cured using Ca2+ ions to form a rigid gel. While the 1:2 and 1:1 samples showed proper shape fidelity, excessive cell concentrations (i.e. the 2:1 sample) resulted in lower resolution and deviation from the intended dimensions. Plant cell-laden scaffolds with various callus content showed high viability and prolonged cell growth over a 35-day culture period, quantified by optical density and imaged by confocal microscopy. The cells implanted in the hydrogel developed into clusters during incubation and exhibited unique texture of artificial plant tissues. Through this approach, the possibility of applying 3D food printing to plant cell culture was verified. The concept of callus-based food-ink provides the promising potential for artificial plant tissue simulation and improves textural properties of 3D printed food similar to real food textures by developing a plant cell-laden hydrogel model.