When it comes to bags, leather may still be the material of choice for most fashion designers, but now there’s another option for those who are more environmentally conscious.
Researchers at Boras University in Sweden have found a way to make sustainable artificial leather from fungi that feed on stale bread, mushrooms in the manufacture of paper products and cotton substitutes, with properties similar to traditional materials.
To create the new material, the researchers used the spores of a fungus called Rhizopus delemar, which is usually found in spoiled food. They fed the mushrooms unsold supermarket bread, then dried and ground it into breadcrumbs and mixed it with water in an experimental reactor.
When fungi feed on bread, they produce a natural microscopic fiber made of chitin and chitosan that builds up in their cell walls. The fungal cells then lay flat and dry to form a skin-like substance.
The prototypes of the fungal skin the team produced were thin and not flexible enough, according to Dr. Akram Zamani of Boras University in Sweden, who led the study, and the group is now working on thicker versions consisting of in multiple layers to get closer. imitate the skin of a real animal.
These compounds include layers treated with tree-derived tannins, which soften the structure, along with layers treated with alkali, which give them strength.
The elasticity, strength and shine are also improved by the glycerin treatment and the bioadhesive”. Our recent tests show that fungal skin has mechanical properties quite similar to those of natural skin, for example the ratio between density and Young’s modulus, which measures hardness, is similar for the two materials,” says Zamani.
And this is not the first substitute for leather made from mushrooms. For example, San Francisco-based biomaterials company MycoWorks last year unveiled a fake skin made from mushrooms, the tubular filaments found in mushrooms. However, Zamani states that most of these commercial products are made from mushrooms harvested or grown in a thin layer on top of food. waste or sawdust by solid state fermentation.
These methods require several days or weeks to produce enough fungal material, whereas mushrooms are submerged in water and only take two days to produce the same amount of material. Also, some fungal skins on the market contain environmentally harmful coatings or reinforcing layers made of synthetic material. petroleum-derived polymers, such as polyester.
Zamani explains that this is in contrast to his team’s products, which are made up of only natural materials and therefore will be biodegradable.