Technology for mushroom cultivation
General information on conditions for growing mushrooms on spent coffee grounds
In order to grow mushrooms on coffee waste you need certain circumstances. In traditional cultivation methods you need bacterial control at high costs, but since the coffee ground is exposed to hot water, bacteria are already reduced to a minimum. Farming mushrooms on coffee spent is 80% more energy efficient than preparing substrates to grow mushrooms on, since it uses free energy needed to prepare the coffee (Pauli, 2010).
Although there are companies that grow mushrooms on coffee, the ideal circumstances are often kept secret from public. Rotterzwam offers an internship of 1 week for 750 euro’s to learn about cultivation methods and growth conditions to prevent other entrepreneurs to make the mistakes they made in the past. It took Rotterzwam 8 months to figure out the ideal conditions through trial and error (Rotterzwam, 2014).
There are different types of coffee residues, which each have their own nutrition and harmful substances. Coffee husk and pulp contain large amounts caffeine and tannins which are harmful for mushroom and inhibit growth of mycelium. Spent coffee grounds are therefore the best type of residue and do not require caffeine removal.
Growing conditions for oyster mushrooms
According to growveg.com you need 500g of oyster mushroom spawn to each 2.5kg of spent coffee ground. At every growing state different circumstance are needed. To prevent mold spores from getting in, which can damage the harvest, fresh coffee ground needs to be used. In the first stage the mushroom spawn with coffee ground needs to be placed in a dark room with 18C-25C degrees. After three weeks the coffee and spawn mixture has become white. If it has become green, molds have been able to grow and the mixture should be thrown away. When the mixture is completely white, it must be placed on a place with fresh air and little light, like a worktop. Twice a day, the area needs to be sprayed with water to prevent the oyster mushrooms from drying out. Damp and humid conditions stimulate growth off mushroom. Therefore often swimming pools or saunas are used for growing mushrooms, like Rotterzwam uses the tenantless swimming pool Tropicana in Rotterdam. A week later, little mushrooms will arise which will double in size every week (Sayner, 2012).
Growing conditions for shiitake mushrooms
To grow shiitake mushrooms, coffee residues are often mixed with additional cellulosic substrates such as sawdust and rice or wheat to create a desirable texture. Mixture formulas can be found in the figure below. For shiitake 0.3 kg to 0.5 kg can be harvested from 1kg dried substrate. The containers with the mixture should be sterilized at 95 degrees for 9 to 10 hours. Once the spawn is added, the containers/bags with the mixture and spawn should be carried to the fruiting house once the white mycelium covers the full surface. Here the shiitake mushroom can grow and can be watered directly once the bodies have grown 2 cm in diameter (Fan, 2005).
Technology needed for controlling the environment
To start a batch you need fresh coffee residual to prevent molds from coming in. Temperature and light control is needed to adapt circumstances to each growing phase. Humidity control and an irrigation system are needed to water the mushrooms, once they have grown. This makes old swimming pools are sauna’s the ideal place to start. Since all technology for cultivation of mushrooms on coffee waste already exists, this part of the design can already be implemented in 2020.
Introduction of the stakeholder Texelse Paddenstoelenkwekerij
The ‘Texelse Paddestoelenkwekerij’ offers daily tours at 16.30 pm. Here shiitake mushrooms are cultivated through craftsmanship in a cultivation barn on Texel’s countryside with manual cultivation. Maarten Dijker founded the company in 2008 and cultivates shiitake mushrooms throughout the whole year (VVV, 2014). Currently he uses sawdust, Oakwood, water and spores in order to grow shiitake mushrooms. The mushrooms are cultivated in a closed room, which is kept at a constant temperature. Oakwood is sterilized, spawn is added, and the mixture is put in plastic bags for 8 weeks. After 15 weeks the full grown mushrooms can be harvested (VVV, 2014).
The ‘Texelse Paddestoelenkwekerij’ already has a fixed network or restaurants that make dishes of shiitake mushrooms, which are spread on the island as the map suggests (Texelse Paddestoelenkwekerij, 2011). Maarten Dijker is known on Texel as a local food producer who receives attention at culinary cooking fairs and tourist attractions. Shiitake mushrooms can be baked with olive oil, used in soup or sauces, baked with fish, lam, beef and hearty cake, which is seen as local Texel cooking (Texelvakantietv, 2011). Maarten Dijker sells the mushrooms to renowned restaurants on and off Texel. Shiitake mushrooms are healthy since they lower cholesterol and blood pressure. It is rich of vitamin B12, which makes it an ideal substitute for meat (Texelse Paddestoelenkwekerij, 2011). Shiitake mushrooms can be kept in the refrigerator for one to two weeks.
YUPTA analysis on Texelse Paddenstoelenkwekerij
Since Maarten Dijker has not been interviewed yet, it is hard to estimate what drives him to convince him to join the project. However based on background information some assumptions can be made on what might be attractive for Texelse Paddenstoelenkwekerij. For example it can be assumed that Maarten Dijker is interested in energy effective solutions. An article indicates that Maarten Dijker has bought an energy sufficient refrigerator, since he believes it is an investment that saves costs in energy on the long term. In this article Maarten Dijker tells that he had visited a meeting by Stichting Duurzaam Texel, indicating he is interested in sustainable cultivation (SenterNovem, unknown).
The role of Maarten Dijker in the system for using coffee waste is quite important, however since Maarten Dijker already supplies shiitake mushrooms with a more traditional method. Since Maarten Dijker is often mentioned in culinary fairs for local food production and offers tours as a tourist attraction, reputation seems to be very important for Maarten Dijker to sell shiitake mushrooms.
The first notification of the typical Texel last name ‘Dijker’ comes from a source of 1609 (Miriam, 2001). It could be possible that Maarten Dijker descends from a family which has a long history on the island of Texel. This could mean that Maarten Dijker attaches a lot of value to Texel culture and wants Texel to become self-supportive. However since in an article Maarten Dijker mentions costs savings as the main reason for buying energy sufficient refrigerators, a self-supportive Texel might have a lower priority than cost savings. Since growing mushrooms requires not much action during cultivation, engagement is not estimated high.
Synchronizing performance with the hospitality industry and integrating rhythm however is important. Texelse Paddenstoelenkwekerij needs fresh spent coffee, while the hospitality industry needs the shiitake mushrooms to prepare the dishes for the day. The exchange of resources could happen in the morning.
The environmental impact is very important to Maarten Dijker, since creating the right environment is vital for the mushrooms to grow. The quality of how Maarten Dijker creates the environment, determines the quality of the mushroom harvest. Since Maarten Dijker lives from cultivating mushrooms, respiratory is estimated high. Tuning is important to build a relationship with restaurants to make sure both stakeholders can rely on each other to deliver a constant resource stream for production.
YUPTA analysis on hospitality industry
The role of the restaurants is important, since they have to deliver the coffee residual. Since reputation is important, restaurants can attract visitors by promoting it uses biological produced shiitake mushrooms cultivated on waste. Restaurants have to be engaged to create a more self-supportive sustainable Texel by closing bio-cycles. The values of the YUPTA cycle concering time are the same for the restaurant as Maarten Dijker, since both are dependent on each other.
Although the restaurants have to give the coffee waste to Maarten Dijker, they do not transform the coffee waste into a valuable resource. Therefore environmental impact is estimated lower. The quality of deeds however is important, since the fresh coffee spent has to have little contamination of molds. It is therefore important that restaurants handle the coffee waste hygienically. The more hygienic they handle the coffee waste, the larger the shiitake mushroom harvest.
Estimate available coffee waste
According to Gro Holland 80000 ton coffee residual is wasted every year in the Netherlands (Gro Holland, 2014). On 14 December 2014 the Netherlands counted 16910968 inhabitants. This means that yearly 4.73 kg of coffee waste is generated per habitant. On 1 November 2014 there were 13597 inhabitants on Texel, meaning they generate 64313 kg of coffee waste a year.This results in 13g of coffee waste a day. Yearly 800.000 visitors visit Texel (Ecomare, 2014). Assuming they visit Texel for one day, this leads to an additional 1040 kg of coffee waste. This leads to a total amount of 65353 kg coffee waste a year. Since some visitors may visit Texel for more days, this amount is likely to be larger.
Assuming you use the coffee waste for shiitake mushrooms (ratio 0.3 to 0.5 per 1kg coffee waste), it means you can deliver 19606 kg to 32676 kg of shiitake mushrooms a year. Currently the Texelse Paddestoelenkwekerij delivers to 13 restaurants, resulting in 1508 kg to 2513 kg which can be sold to each of them yearly. Daily this means there is 4.1 kg to 6.9 kg available for each restaurant. If you need 150 gr of shiitake mushrooms for each menu you can serve 27 to 46 dishes a day. In case this is not sufficient the traditional method of cultivation by Texelse Paddenstoelenkwekerij can be used as well. Shiitake mushrooms that become wasted can be composted again. The advantage for the Texelse Paddenstoelenkwekerij is that cultivation on coffee waste is cheaper since sterilization is not necessary when you use fresh coffee spent. The cultivation on coffee spent can attract more tourists for the tours Maarten Dijker organizes in his company, which results in higher income.
Actions needed by stakeholders
In this scenario both actors become depended on each other, since waste of the hospitality industry becomes a resource for the hospitality industry again through the Texelse Paddenstoelenkwekerij as an intermediary. Since the hospitality industry benefits from shiitake cultivation and the coffee waste is wasted anyway, the hospitality industry can give the coffee waste to Texelse Paddenstoelenkwekerij for free. This could make the deal interesting for Maarten Dijker, since production cost are lowered since the sterilization process is not necessary when using the free coffee spent.
Maarten Dijker already supplies the hospitality industry with shiitake mushrooms, meaning there is already transport available. To collect the coffee waste it is the easiest to use the existing delivery moments of the shiitake mushrooms. Through this method Maarten Dijker and the hospitality industry are able to increase shiitake mushroom production on a costs effective sustainable manner.