Laser Cook Fusion: Layer-Specific Gelation in 3D Food Printing via Blue Laser Irradiation

Current 3D food printers struggle with handling liquid food inks due to challenges in maintaining structural stability, controlling material flow, and preventing undesired spreading. This study presents the development of the "Laser Cook Fusion," a 3D food printer that enables the fabrication of intricate food structures through the gelation of polysaccharides using localized blue laser heating. A key feature of this printer is its ability to switch printing materials between layers, allowing for the precise adjustment of food texture and structure. The switching mechanism is achieved through a controlled dual-material deposition system, ensuring seamless transitions between different food inks. Additionally, a cleaning process during layer transitions prevents ink contamination, enhancing the accuracy of the layered structure. To evaluate the scientific validity of this approach, we systematically analyzed the mechanical properties and printability of various food inks, including curdlan, tomato, pumpkin, and ukogi powders. Among them, tomato-based ink exhibited the highest rigidity, with a peak average rupture force of 5.72 +/- 0.37 N in the vertical direction. Ukogi powder also demonstrated high mechanical strength, reaching 5.48 +/- 0.35 N in the same direction. In contrast, a layered mixture (Mix) exhibited moderate rigidity, with direction-dependent variations and a peak rupture force of 2.04 +/- 0.08 N. The ability to combine different materials allowed for tunable hardness, demonstrating the potential for customized food textures. Furthermore, we demonstrated the printer's capability in preparing complex Japanese cuisine, such as mille-feuille-style Japanese cakes.