In an derelict swimming pool in the harbour Rotterdam a company grows Oyster mushrooms. The company RotterZwam (‘Rotter’ for Rotterdam, ‘Zwam’ being the Dutch word for mushroom) installed a mushroom-growing system in the locker rooms of the swimming pool. The two entrepreneurs collect coffee grind from cafes and restaurants within Rotterdam, mixes it with mycelium of the desired mushroom, puts it in bags and hangs them up in the climate controlled rooms.
The company has moved on from the start-up phase by giving training, publishing books and the sales of home-growing systems for mushrooms.
Since the production of mushroom on coffee grind is unusual, it raises questions. Consumers wonder whether the mushrooms contain caffeine, or even heavy metals or pesticides. Such questions are common for new, urban initiatives in food production. Innovation is often at the heart of urban farming initiatives. But innovation raises questions, which are often costly to properly address. Such costs will then form a blockade in the consumer acceptance and further market development of the initiative. Wageningen UR Greenhouse Horticulture supports innovative concepts in Urban Horticulture.
The topsector program in The Netherlands enabled a project on Urban Horticulture (PPS-Stadstuinbouw) to support initiatives. In this case we analysed the product for all possible contaminants and concluded that the product was safe by European standards. Oyster mushrooms from Rotterdam’s coffee grind are therefore safe (and tasty)!