Meet the mushroom that could one day replace plastic

Here’s one more reason to love a good mushroom: one day, you might be able to make headphones, memory foam for shoes, or even aircraft exoskeletons with it. Researchers just assessed the engineering possibilities with one particularly impressive mushroom and found that it might be able to replace plastic in a whole bunch of different use cases.

Using mushrooms instead of plastic could cut down on the mountains of waste humans create. Plastics made out of fossil fuels are actually really difficult to recycle and usually wind up cluttering landfills, landscapes, and waterways. Materials made with mushrooms, on the other hand, would be biodegradable and could be reused at the end of a product’s life to make more of the same stuff.

The fungus Fomes fomentarius is the focus of new research published today in the journal Science Advances. It has the remarkable ability to yield a wide range of materials with different properties — from soft and spongelike to tough and woody. By studying the architecture of the mushroom, researchers hope to pave the way for it to become a more sustainable building block of our lives.

“We were really amazed with the structure because one thing that you immediately notice if you’re a biologist is that when something that beautiful starts to form, nature just doesn’t do it because of how nice it is — there must be a function there,” says Pezhman Mohammadi, one of the authors of the new paper and a senior scientist at VTT Technical Research Centre of Finland.

In the wild, F. fomentarius might look like a horse’s hoof growing out of a tree trunk. Humans have already used it for thousands of years as tinder for starting fires. That’s how it earned the nicknames hoof fungus and tinder fungus. In the future, it could also be used to create a new class of ultra-lightweight high-performance materials, the new research shows.

What’s unique about this fungus is that it has three layers with distinct properties that could each be useful in different ways. There’s a very tough outer crust that could be used to make impact-resistant coating for windshields, for example. Then, according to Mohammadi, there’s a soft middle layer that feels good on the skin and could replicate leather. The third inner layer is similar to wood. The research team used advanced imaging techniques and mechanical strength tests to study each layer and assess their potential uses.

There’s already growing interest in mushroom-based building materials, packaging, and textiles. And Mohammadi and his team have already created a prototype set of headphones using the thread-like structure, called mycelium, that makes up a fungus.

Of course, there’s still a long way to go before mushrooms can replace plastic. You can’t harvest them from forests because it would do too much damage to the ecosystem. The mycelium would have to be mass-produced for market. Plus, you might want to tweak the fungus’ genome to emphasize certain traits. And there’s more research and testing to be done to make sure the resulting materials strike just the right balance of being both biodegradable and durable enough for consumers.

The hope is that mushroom-based products will break down once they’re no longer useful instead of lingering indefinitely like a lot of plastic pollution. As waste, products made with fungus can even become food for new mycelium production, creating a closed-loop manufacturing process. That’s sort of the gold standard for making any consumer product at least a little more sustainable.