How a sustainable food business mushroomed out of recycled coffee granules

Paddy Arnold of Revolution Farm & Kitchen, which has joined forces with UCD, says that the appetite for urban farming is growing

Take some used coffee granules, a repurposed food refrigeration container and a bustling university campus, and what do you get? Potentially, mushrooms.

It is a brave new world of urban farming in which less-agrarian environments can still churn out appetising ingredients, not to mention the potential environmental benefits.

Revolution Farm & Kitchen, a modest venture whose own growth was nourished in a side room of a Dublin house, has now joined forces with UCD Innovation Academy, which was quick to recognise its message and values.

“I don’t know if we’re doing [urban farming] as well as, say, other countries but I think there’s certainly an appetite for it,” says Paddy Arnold, the 36-year-old gastro entrepreneur whose ambitions of opening a restaurant, derailed by Covid-19, were quickly turned to tackling agricultural solutions.


There is certainly an appetite for his produce. A rapidly developed, if modest, business, Revolution began churning out sauces from its own stock of oyster mushrooms. The coffee granules were bagged up at a Ranelagh cafe and used to grow the mushrooms, which were used to make sauce which was fed back to the same cafe and others.

Arnold, together with business partner James Egan (36), initially began experimenting on a small scale in 2020 before moving their concoctions to grow bags and eventually to a 45ft retrofitted truck container.

The process involves combining spent grounds with wood shavings and mushroom spawn in cement mixers before leaving it to incubate and pop out the sides of punctured wheelie bins, where they are harvested.

“There’s a lot of waste in kitchens, a lot of food waste and maybe there’s ways to [address] that so that was really my focus and I had some time to think up some ideas and research some various things,” says Arnold of the motivation behind the company. “We came across this idea to growing mushrooms from coffee grounds.”

After beginning to sell their sauces, the duo were looking for a home to park their container farm when the UCD Innovation Academy came calling. Its founding director, Prof Suzi Jarvis, discovered their produce and, seizing on its educational growth potential, brought the Revolution to campus.

In a short promotional video, the company notes the dual education of mushroom and enterprise growth, and how students can gain exposure to “what’s involved in starting up a new business, particularly in the area of sustainability”.

Revolution is now handing over its operation to the academy. While its exact future has yet to become clear, it is expected to form part of a newly envisaged sustainability “living lab” alongside a biodigester and a plastics recycling unit.

Although Arnold can list off several ventures dabbling in urban food production in Dublin and Cork, the industry remains at a relatively nascent stage in Ireland.

He is now switching his focus once again to opening a restaurant that will probably promote the kind of sustainable practices he has championed. He aims to continue making his sauce, too, just with different mushrooms.

Mark Hilliard

Mark Hilliard

Mark Hilliard is a reporter with The Irish Times