Brussels entrepreneurs grow mushrooms in coffee grounds


The Brussels project Permafungi has found a sustainable answer to the plentiful by-product of our national addiction to coffee

“The perfect marriage”

In Belgium, we like our coffee. Consumption averages over seven kilograms a year per person. This love affair makes for a large amount of coffee grounds, but a new Brussels business has developed a project that gives this plentiful by-product a second life.

Two Martins – Martin François and Martin Germeau – are the brains behind Permafungi, an innovative agricultural project that grows oyster mushrooms in a mixture of coffee grounds and straw.

Permafungi combines fungi, the Latin term for mushrooms, with perma, a contraction of permaculture. For those of us whose school science has receded into the distance, permaculture is about developing agricultural systems that are sustainable and self-sufficient.

Permafungi traces its origins to early 2013 when Germeau, a bio-engineer by training, and at the time volunteering at a permaculture project in Thailand, started considering ways to make permaculture a reality in his native Brussels.

François, also far from home in Montreal, was searching for a project with a social aspect. By chance, the two met online and subsequently developed the business.

Another home-grown success, organic eatery chain Exki, seemed a natural place to source the raw material. A cargo bike makes a round of 10 Exki outlets to collect the coffee grounds. “Oyster mushrooms and coffee are the perfect marriage,” says Germeau. 

Walking down into the cool, cavernous cellars of the Tour&Taxis near the canal, Germeau (pictured left) explains why Brussels is the perfect location for a project like Permafungi. “Mushrooms cultivation needs dark, temperate conditions, and so lends itself very well to an urban environment – a warehouse or a basement, for example,” he explains. “We are very fortunate that Tour&Taxis agreed to rent us some of their underground space.”

Ready to sprout

With similar ventures in the US, Berlin, Portugal and the Netherlands, there is a small but committed global community with which to tease out teething problems. “There is healthy competition but also a lot of co-operation,” Germeau says.

There are no secrets here; we are happy to share our knowhow

- Martin Germeau

“We were in contact with a similar start-up in Rotterdam that was attempting to use a combination of straw and coffee grounds with little success. Permafungi at the time was making no progress using a mix of coffee bean husks and grounds. So we did a sort of swap and found that the straw technique was ideal for the conditions in Brussels, while in Rotterdam their breakthrough came when they tried the coffee husks.”

The final piece in the Brussels’ production puzzle fell into place when the two founders borrowed the process of sterilising the straw from a US operation.

Co-creation has been a watchword from the outset, and, in two years, Permafungi has matured into an urban permaculture success story, with five staff, a multitude of volunteers and a healthy dose of goodwill.

But production is just one pillar; Permafungi is also committed to educating the public through workshops and tours, as well as promoting domestic cultivation of oyster mushrooms through their “ready-to-sprout kits”.

“There are no secrets here, as can often be the case with mushroom cultivation,” Germeau says. “We are happy to share our knowhow.”

A labour of love

After a walk along dark, flagstone corridors, we arrive at the hub of production, where Germeau explains the three-step process involved in oyster mushroom cultivation. Over the mechanical hum of the ventilation system supplying purified air, he breaks down the science behind the planting, incubation and, finally, sprouting of the mushrooms.

Because of the highly sterile conditions, the closest we get to the planting stage – where the mushroom seed is mixed with coffee and straw – is a wave to the lab technician in white overalls and mask. Incubation, equally inaccessible, is the three-week period during which the mixture matures in complete darkness.

The final stage, the “fruiting”, or sprouting of the mushrooms, is more impressive to the casual eye. In a light, humid room, large sausage-shaped plastic bags are suspended from the ceiling in rows. Sprouting out from the plastic at haphazard angles are florets of oyster mushrooms. The young sprouts are dark, but as they grow, they fade to an off-white – let’s just say it – mushroomy colour.

Permafungi’s mushrooms are harvested seven days a week. They work with a local distributor specialised in permaculture and also sell direct to the Terrabio organic market on Huidevettersstraat and the two Brussels branches of the co-operative supermarket Färm.

You'll also find their shrooms at the Tour&Taxis restaurant and at Brussels raw food eatery YAG. As the team have refined their technique, mushroom production tripled between January and March of this year. 

Work in progress

Each sausage-shaped pack produces two or three yields, and the used mix is then passed on to the nearby urban farm in Maximiliaanpark, where it becomes fertiliser. Thus, production and sustainability are largely in harmony at Permafungi.

Any biodegradable plastic would be destroyed by the fungus

- Martin Germeau

“Our one problem is the amount of plastic we use. Any biodegradable plastic would be destroyed by the fungus, so we have no option but to use traditional plastic,” says Germeau. “Developing a longer-lasting compostable plastic would be interesting research, but, even if it were viable, it would take some years to develop.”

Germeau acknowledges that establishing their start-up came with some administrative challenges. “As we’re unusual in carrying out agricultural production in an urban environment, it’s often a case of interpreting existing legislation that doesn’t correspond exactly and finding the best fit.”

As a parting gift, Germeau twists a stem of oyster mushrooms off and proffers it with the advice “chop roughly and sauté in a little oil”.

Photo courtesy Permafungi