This Mushroom Grown Fabric Could Replace Leather

A fabric grown from fungal threads in a fermentation tank can be turned into something strong enough to make a handbag, and in laboratory tests, it biodegraded rapidly in aquatic conditions. That is the central finding of a new study published in the journal ACS Applied Bio Materials by researchers at VTT Technical Research Centre of Finland, who have demonstrated a pilot-scale production process for mushroom-based fabric that could one day compete with animal leather in fashion, automotive, and interior design.

Environmental math like this is hard to ignore. In the study’s comparative tests, cow leather broke down by only 15% in aquatic conditions over 119 days. A conventional vinyl-cotton fabric managed just 35% over the same period. The mushroom-based material, by contrast, reached 77% biodegradation in 28 days under the same conditions and fully disintegrated within six weeks in an industrial composting environment held at 58 degrees Celsius. Researchers caution a full environmental comparison to leather has not yet been done.

Fungi have long attracted attention as a building block for next-generation materials. The dense, thread-like root network fungi produce, called mycelium, naturally forms a branching, fibrous structure rich in carbohydrates and proteins that can be coaxed into a fabric-like sheet. Turning that biology into something a manufacturer can produce at scale has remained elusive, and this new research moves concretely in that direction.

Mushroom Fabric Gains Strength From a Wood-Fiber Additive

Researchers used a specific fungus, Trichoderma reesei, already common in industry for producing enzymes, because it grows efficiently in liquid fermentation tanks and forms a fine, pulp-like mass. In smaller lab cultures, the process typically yielded 5 to 6 grams of dry material per liter of liquid over five days. Scaled up to tanks holding 10 to 20 liters, one extended run reached 45 grams per liter. Getting the larger batches right took some trial and error, since small changes in how the fungus was grown could make the resulting fabric noticeably stronger or weaker.

Once harvested, the wet mycelium pulp was mixed with additives and poured into molds, then dried with heat into flat sheets. Mycelium alone made sheets too stiff and brittle to use. Adding sorbitol, a natural sugar alcohol used as a softening agent, produced flexible sheets that stayed stable in storage. Most other additives tested did little for strength. Nanofibrillated cellulose, wood fiber broken down into extremely fine strands, was the exception: it produced sheets that were both stronger and more flexible, an unusual combination since reinforcing materials typically improve one property at the expense of the other.

A critical discovery was that how the pulp was washed before forming into sheets changed the final material’s quality dramatically. Simply rinsing the pulp before adding the wood fiber, and rinsing it with a bit of methanol beforehand, produced the strongest results in the study: about 19 megapascals of tensile strength with around 10% stretch before breaking. Chrome-tanned cow leather typically falls between 8 and 15 megapascals, so on raw strength, the mushroom fabric is competitive, and even ahead of some leather. Stretch is another matter: cow leather stretches 37 to 68% before breaking, far beyond the 10% the mushroom fabric currently achieves, an area the authors flag for further work.

Prototype Handbag Shows Mushroom Fabric Can Be Cut, Dyed, and Stitched

To show the material’s versatility, the team demonstrated several finishing options. Colorants mixed into the formulation before drying produced green, red, and black sheets. Textured surfaces came from casting the material onto patterned silicone mats. Sheets were also cast onto woven cotton textiles to create a two-layer material with better tear resistance. From those textile-backed sheets, the team assembled a prototype handbag with a wooden handle, proof the material can survive real cutting, stitching, and assembly.

Pilot-Scale Casting Line Produces Mushroom Fabric at a Meter Scale

A pilot-scale film-casting line, the same type of equipment already used in paper coating and film manufacturing, delivered the most industrially telling demonstration in the study. The wet mycelium formulation flowed onto a moving plastic surface traveling at one meter per minute, spreading into a sheet and drying as it went. Test runs produced sheets roughly 0.22 meters wide by 8 meters long, in uncolored and black-dyed versions. Full roll-to-roll winding could not be demonstrated because the moving plastic belt could not handle the required heat, an engineering challenge the authors flag for future work.

Researchers are candid about what still needs to happen before mushroom fabric reaches store shelves. Tear resistance and abrasion resistance need formal testing and likely improvement, and while the biodegradation results are in, no one has yet done the broader accounting of energy, water, and resources needed to say for certain that making this fabric is gentler on the planet than making animal leather.

For now, the proof is in the prototype. A handbag stitched from fungus, built to hold its shape on a shelf, and shown in lab tests to disintegrate rapidly once industrial composting takes over.

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