Multi-wavelength laser texturization with 3D-printed foods

Organoleptic evaluation plays a crucial role in our perception of food. Our sensory experiences are not solely determined by taste, but rather by the integrated inputs from all of our senses—taste, sight, smell, hearing, and touch. Multi-ingredient food printing is an emerging technology that enables the creation of novel flavors and unique food combinations. While this technology shows potential for developing customized, nutritious meals and plant-based meat analogues, it faces challenges in replicating textures that are perceived as ‘crunchy’ or firm, which are key factors influencing consumer acceptance. This study investigates the use of blue ($\lambda$ = 445 nm), near-infrared ($\lambda$ = 980 nm), and mid-infrared ($\lambda$ = $10.6\mu m$) lasers as thermal processing tools for texturizing 3D-printed foods in situ. We found that modulating the frequency of laser exposure across printed layers allows for precise control over elasticity and chewiness throughout the printed product. Firmer textures were achieved with more frequent laser exposure, and compression testing validated that laser-cooked samples exhibited peak elasticity at mid strain (5%–10%), while oven-baked samples were firmer at high strain (20%–30%). Additionally, we demonstrate in situ cooking of a complex, multi-ingredient 3D-printed three course meal (14 ingredients). Our findings highlight the importance of controlling food texture to enhance the sensory experience of 3D-printed foods, which remains a critical challenge for broad consumer adoption.