Are mushrooms the future of alternative leather?

In 2007, Philip Ross, a Bay Area artist, was preparing for an exhibition. It demonstrated his work with ‘mycotecture’, the creation of materials through the manipulation of mycelium, the substance that forms the root structure of mushrooms. Mr. Ross purchased mushroom spores from local farmers and persuaded them to grow into a substance he describes as akin to medium density fiberboard. In preparation for the exhibition, he met Sophia Wang, then a Ph.D. student at the University of California, Berkeley, who helped him produce the show.

Mr. Ross continued to experiment with mycelium and in 2012, after receiving requests from multiple companies interested in the technology, Mr. Ross asked Ms. Wang to co-found MycoWorks with him to commercialize his mycotecture technique. They co-founded the company the following year, while Ms. Wang was finishing her dissertation.

At first, “the three of us were in a plywood and plastic sheeting basement,” says Ms. Wang, who is now the company’s head of culture. “We were a start-up biotech company, but we were created by artists.”

MycoWorks ultimately focused on creating a material that had the look and feel of leather, but was free of animal parts. Called Reishi, after the Japanese name for the genus of mushrooms that Mr. Ross used for the first time, it can currently be produced in 1.8 square meter sheets. (MycoWorks declined to disclose prices, other than to say it’s currently on par with exotic skins. As the company continues to grow, she added, MycoWorks will be able to offer some at lower prices.)

Headquartered in Emeryville, California, the company has filed more than 75 patents and now has more than 160 employees in the United States, France and Spain. It has also forged partnerships with high-end companies such as Hermès and, most recently, furniture maker Ligne Roset and GM Ventures, the investment arm of General Motors.

If it continues to scale, MycoWorks has tremendous potential: the leather goods market exceeded $400 billion in 2021 and is expected to exceed $720 billion by 2030.

Then there’s the global market for synthetic leather materials, which is projected to reach nearly $67 billion by 2030, according to Research and Markets, a source for data and analysis. The so-called biobased leather market, containing only naturally occurring material, was estimated by Polaris Market Research to be worth about $650 million by 2021. But that number may be too low, according to Frank Zambrelli, the executive director of the Responsible Business Coalition at Fordham University in New York, as well as a general manager of the consulting firm Accenture. “I sincerely believe they do not accurately reflect market and consumer interest in the category, nor advancements in the technology and quality of the emerging products,” he said.

To date, many of the leather alternatives are made from plastics, polyurethane or polyvinyl chloride (better known as PVC), sometimes resulting in the derisive term “pleather.” But the bigger problem is that those who use plastic are generally environmentally unfriendly and don’t offer a sustainable option.

In contrast, MycoWorks “can achieve the same quality and performance as animal leather without the need for any kind of plastic,” Matthew Scullin, MycoWorks’ CEO, said at a temporary exhibition showroom in New York in the spring. The company is now too big to rely solely on local farmers for mycelium supplies and has its own varieties that “we basically keep in cold storage,” Mr Scullin said.

The process begins by combining the mycelium with sawmill waste in trays; as the sawdust decomposes, the mixture begins to develop into a thin sheet. The material can then be customized to customer specifications, including specific textures, and may include the addition of other fibres, such as cotton. The Fine Mycelium, the trademarked name for its patented technology, is then finished by third-party tanneries. (The tanning process does not use chromium, historically one of the most polluting parts of leather production.)

Because the Reishi-making process has only a few steps, Mr. Scullin has a “low impact” on the environment. In addition, he said, while animal skins vary in size and texture, Reishi is more consistent and predictable for customers.

In August, MycoWorks broke ground on construction of a 15,000-square-foot factory in Union, SC. Upon completion by the end of 2023, it will begin producing on a large scale – several million square feet of reishi per year. Construction is supported by new investments. MycoWorks closed $125 million in new funding in January. With the new factory, the company can meet the increasing demand; Mr. Scullin says it has received thousands of inquiries from potential clients.

One client Reishi has already taken on is fashion house Hermès, which styles and colors the fabric (which it calls Sylvania) for use in its Victoria handbags. (The company declined to comment on how much it bought or the price of the bag, which is no longer listed on their website, compared to a bag that used leather.)

Nick Fouquet, a designer milliner based in Venice, California who is popular among celebrities, used Reishi in some of his hats this year. “I asked one of my seamstresses and she couldn’t tell the difference between Reishi and genuine leather,” he said. He produced 50 bucket hats made entirely of the MycoWorks material, and at a price of $810, they sold out. He said he hoped to reuse the fabric in future seasons.

The automotive industry also represents a huge opportunity as car manufacturers are the second largest user of leather after footwear, according to Mr. Scullin. The number of questions increased last year as automakers began introducing new electric vehicles to the market, he added. The partnership with GM Ventures, announced Oct. 18, “aims to advance the development of sustainable automotive materials,” Wade Sheffer, general manager of GM Ventures, said in a statement. (The automaker declined to disclose the size of its investment.)

While Mr Scullin declined to provide further details, he said the deal “is designed not only to change the sustainability profile of cars, but also to modernize the supply chain for these materials” so they can get to market more quickly. To that end, he said, he is considering starting new factories to serve the auto industry.

MycoWorks has competition. Bolt Threads, based in California, also produces a leather-like material made from mycelium and is attracting high-end customers at an impressive rate. Bolt has teamed up with Stella McCartney, known for her avoidance of animal products, as well as Adidas, Lululemon and Mercedes. Other materials scientists are experimenting with bio-based fabrics, including pineapple and cactus.

The companies working with mycelium, said Mr. Zambrelli, “are not trying to duplicate what an animal hide does, but creating something that has the softness and resilience of leather, but something that, fascinatingly enough, is also more manageable.”

And mycelium continues to be used in the fine arts, said Mr. Ross, the founder, who is now chief technology officer. At Mycoworks, Ms. Wang: “The practice is most clearly reflected in our product design and prototypes. That’s how people get really creative here.”