Impact of varying macronutrient composition on the printability of pea-based inks in extrusion-based 3D food printing

Personalized foods with varying macronutrient compositions can be created by 3D food printing to fulfill the dietary requirements of individual consumers. In this work, we aim to quantitatively study the influence of varying multiple macronutrient concentrations on printability of food inks, by applying a systematic approach. Pea-based food inks consisting of insoluble pea fibre, pea protein, and native pea starch were formulated and water was added following these ingredients' respective water holding capacities. Printability was quantified in terms of extrudability (force required to extrude material out of a cartridge), buildability (flow point to deter-mine shape stability after deposition on the printing platform), and printing precision (surface defect index (SDI) of the printed object). This approach helps to efficiently define a printable landscape of pea-based inks with a large variation in macronutrient composition. Our results show that increasing protein concentration resulted in increased extrusion force and flow point, while the opposite effect was found for fibre. Of all the tested pea-based formulations, 71% could be printed to a height of 50 mm with high printing precision (SDI<0.14). The presented systematic approach provides a solid basis for rapid development of printable plant-based inks while avoiding a trial-and-error approach to optimize inks with highly variable macronutrient composition.