Living fungal materials hold great potential within their natural genetic expression, however the concerns of fire development and lack of regulatory standards refences continue to prevent their implementation. Here the role of biofabrication logics unlock emergent properties, through careful observation, bioreactor design, and a deep understanding of mycelial behavior. To which the following work seeks, to transform the now-iconic appearance of mycelium-based materials advancing into the next generation of functional and aesthetic possibilities.

By promoting the auto-densification of aerial mycelium (without mechanical compression) we achieve surfaces that are not only more durable but potentially critical in enhancing fire resistance. Additionally, leveraging species-specific pigments within these densified mycelial mats further contributes to fire-retardant properties. By optimizing growth parameters such as humidity, CO₂:O₂ concentration, air exchange, and nutrient availability, mycelial networks develop densified mycelium mats and reduced internal porosity

Pigmentation, colors, typically arises in similar products from the unregulated local microclimatic fluctuations which allow the undesirable formation of fruiting bodies, mushrooms. Here color formation progresses as an wave front controlled by internal hyphal signals, which can be manipulated to naturally unlock the complete pigment spectrum expression to add value to these Engineered Living Materials, ELMs. While colouration is visually appealing their material properties value becomes apparent when on fire.  

Pigmentation from bio-derived compounds, rich in polyphenolic and mineral constituents, further enhances thermal stability through increased char formation and surface insulation under heat exposure. Preliminary flammability tests demonstrate that environmentally densified and pigmented mycelium composites exhibit delayed ignition and reduced smoldering fire expansion compared to untreated controls. Together these two advancements are making the material more attractive for both consumer and industrial applications.