Integrated design of micro-fibrous food with multi-materials fabricated by uniaxial 3D printing

Owing to the interest in sustainable foods, a new approach known as 3D food printing is being employed to make fibrous foods for meat and fish substitutes. In this study, we developed a filament structure with a multi-material ink comprising fish surimi-based ink (SI) and plant-based ink (PI), using single-nozzle printing and steaming. PI and an SI + PI mix collapsed after printing owing to their low shear modulus, although both PI and SI showed gel-like rheological behaviors. However, unlike the control, the objects printed with two and four columns per filament remained stable and fiberized after steaming. Each SI and PI sample gelatinized irreversibly at approximately 50 °C. The different rheological values of these inks after cooling resulted in relatively strong (PI) and weak (SI) fibers, which constructed a filament matrix. A cutting test demonstrated that the transverse strength of the fibrous structure of the printed objects was higher than the longitudinal strength, in contrast to that of the control. The degree of texturization increased with the fiber thickness based on the column number or nozzle size. Thus, we successfully designed a fibrous system using printing and post-processing and substantially broadened the application opportunities for creating fibril matrices for sustainable food analogs.