Thermoreversible gels – Optimisation of processing parameters in fused Deposition Modelling

3D food printing: monitoring, quality assessment and adaptation with machine vision

“…During preliminary experiments, we failed to print the κ-carrageenan-gelatin blend at higher syringe temperatures due to the spreading and spraying of the liquid material on the platform. A similar observation was made byVadodaria et al (2021) as the authors stated that high printing temperatures (syringe temperatures) led to fast spreading of hydrogel-based printing materials. Due to the sharp sol-gel transition of the κ-carrageenan-gelatin blend (Figure5.2A), a slight overheating leads to rapid decrease in viscosity.…”

“…below the gelation temperature) result in rapid material solidification. The rapidly solidified materials can lead to insufficient layer fusions and surface roughness of the filaments, which are undesirable for the final printing quality (Rando and Ramaioli, 2021;Vadodaria et al, 2021). From our thermographic observations, for 3D food printers without a nozzle heater and without active cooling of the printing platform, we suggest to set the syringe heater temperature just above a material's gelation temperature to ensure proper fusion and consistency of the extruded filaments.…”

“…These phenomena are influenced by several printing parameters such as the printing temperature, the printing speed, the ambient temperature, and the extrusion pressure. The printing temperature and speed are the key parameters reported by previous studies to determine the printability of chocolate and thermoreversible hydrogels (Lanaro et al, 2017;Rando and Ramaioli, 2021;Vadodaria et al, 2021). Improper control of the printing parameters may lead to printing failures such as material spreading, structural collapses, and insufficient fusion between layers.…”