Mycelial growth stimulus-responsive 4D printing: A novel approach for mycelium-based meat analogs fabrication

From the paper

Abstract

Mycelium emerges as a promising sustainable biomaterial for meat analogs, owing to its fibrous structure and rich nutritional profile. This study introduces a novel 4D printing approach that leverages mycelial growth as a biological stimulus to fabricate mycelium-based meat analogs. A printable bio-ink based on soy protein and Pleurotus eryngii mycelia was developed, enabling the fabrication of scaffolds with well-defined porous structures. The bio-ink formulation optimized with 5 % cassava starch yielded a maximum mycelial radial growth diameter of 50.97 mm. Incorporation of 6 % mycelium improved ink rheology, allowing the fabrication of stable, porous structures. A 40 % infill density was optimal for promoting uniform mycelial colonization, during which the fungal network penetrates and integrates with the scaffold, acting as a biological reinforcement. During 10 days of incubation, mycelial biomass accumulated to 18.2 %, leading to a 6.11-fold increase in hardness and enabling in situ texture development. Our work demonstrates that mycelium stimulus-responsive 4D printing is a viable approach for fabricating meat analogs, enabling dynamic modulation of textural properties post-fabrication via precisely controlled biological growth. This study provides a theoretical basis and technical support for developing a new sustainable mycelium-based meat analog, which integrates biological reinforcement and customizable textural properties.