NEW PRODUCT / SOLUTION
Mushrooms
APPLICATION SECTOR
Food and beverage
VALORIZED OUTPUT
Spent coffee grounds
TRL
Deploy
CONTEXT
Global
SDG
VALUE CHAIN AREA
Spent coffee grounds have proven to be a valuable resource in agriculture, particularly as a growing medium for mushrooms. The Department of Architecture and Design at Politecnico di Torino, in collaboration with Lavazza, extensively researched this concept, developing a systemic approach to repurposing coffee waste (Barbero and Toso, 2009). After extracting lipids for pharmaceutical and cosmetic applications, the remaining coffee grounds have been successfully used as a substrate for cultivating edible mushrooms (Pleurotus ostreatus). The post-harvest substrate is then repurposed for vermicomposting, ensuring a closed-loop system with minimal waste.
In vermiculture, worms thrive on spent coffee grounds, especially when combined with other agricultural by-products. These worms process the material into nutrient-rich vermicompost, a high-quality organic fertilizer. Additionally, the worms themselves can be transformed into protein-rich flour for animal feed, a method pioneered by UK-based company Entocycle. Beyond vermiculture, spent coffee grounds have also been incorporated into animal feed. Research indicates that including up to 10% spent coffee grounds in the diets of dairy ewes enhances milk production and composition without negatively affecting digestion or feeding behavior (De Otalora et al., 2020). Similar trials with cows have yielded promising results, as demonstrated by a Starbucks-led initiative in Japan that repurposes spent coffee grounds into cattle feed.
Further demonstrating its versatility, SCG plays a crucial role in mushroom cultivation, serving as a nutrient-rich growing medium. The process begins by mixing the grounds with water, chalk, coffee husk, and mushroom spawn. The mixture is then placed into large bags and suspended in a controlled environment, allowing mushrooms to develop within three to six weeks. The nutrient-rich composition of coffee grounds, which includes nitrogen and essential minerals, provides an excellent substrate for mycelium colonization, fostering healthy mushroom development.
Sources:
- Barbero, S., & Toso, D. (2009). Buone previsioni dai fondi di caffè. Ricerca applicata alla coltivazione dei funghi dai fondi di caffè. Time&Mind Press. ISBN 978-88-903392-6-4
- De Otálora, X. D., Ruiz, R., Goiri, I., Rey, J., Atxaerandio, R., San Martin, D., Orive, M., Iñarra, B., Zufia, J., Urkiza, J. (2020). Valorization of spent coffee grounds as functional feed ingredient improves productive performance of Latxa dairy ewes. Animal Feed Science and Technology, 264, 114461. https://doi.org/10.1016/j.anifeedsci.2020.114461
- ICO 2024, Beyond Coffee: Towards a Circular Coffee Economy coffee-development-report-2022-23.pdf
DESCRIPTION
IMPACTS
The natural acidity of spent coffee grounds may not be suitable for all mushroom species, often requiring pH adjustments through the addition of amendments. Additionally, residual caffeine in the grounds could potentially impact mushroom growth or quality. Furthermore, regulations governing the use of spent coffee grounds as a cultivation substrate vary across regions, necessitating compliance with local agricultural standards to ensure safe and effective implementation.
CHALLENGES AND LIMITS
EXAMPLES OF APPLICATION
A Portuguese company focused on reducing food waste, particularly coffee waste. They produce kits for home growers interested in cultivating mycelium and medicinal fungi.
Launched in 2011 by Ressources Humaines Sans Frontières, a French health care organization for people with disabilities, the project uses spent coffee grounds as compost for mycelium growth and fungi production, which are later served in Michelin-starred restaurants in Paris.
A Netherlands-based company in Rotterdam that produces fungi and by-products using spent coffee grounds. Their offerings include fungi-based snacks, specialty beers, and personal care products.
Cupmena
Footprints Africa, ACEN
Egypt/Africa , 2022
A project in Egypt developing waste collection systems to cultivate fungi from spent coffee grounds. This initiative is part of broader collaborations with Footprints Africa and the African Circular Economy Network (ACEN).
An urban mushroom farm established in Exeter in 2013, now based in Devon. The company produces mushrooms and extracts, provides kits and courses for fungi cultivation, and developed a resource hub for knoweldge sharing. Substrates include spent coffee grounds.
Coffee 4 Planet Ark in Sydney, Australia, is running a feasibility study on a circular economy system for spent coffee grounds (SCGs) with local cafes and coffee companies in Sydney and Melbourne. The project aims to prevent landfill waste and cut emissions by ~600 kg CO₂e per ton of coffee collected. Further details are in the feasibility study and trial report.
An Italian company founded in 2019 that collects spent coffee grounds in the cities of Sassari and Alghero. These SCGs are then used for mycelium cultivation in Tuscany, and the resulting fungi are sold to gourmet restaurants.
From 2007 to 2009, Politecnico di Torino and Lavazza developed a systemic approach for (CVC) aiming at giving value to spent coffee grounds as substrate for mushroom farming. In 2012-2013, Lavazza co-funded another feasibility study: starting with the harvesting of the grounds, the project articulates several possible industrial processes leading to the introduction of new products on the market and new gains from a raw material destined for disposal. The mushrooms have also been cultivated during Expo 2015 in Milano.
The company was born from a pilot project that explored the use of coffee grounds as a substrate for mushroom cultivation, with a view to circular economy and sustainability.
Il Giardinone has embraced a circular economy since 2015, focusing on sustainable innovation. Key projects include transforming used coffee grounds into fresh mushrooms (Fungo Box) and new materials (Coffeefrom). They also develop collective composting projects, promoting ecological transition and knowledge exchange between profit and non-profit sectors.