At a time when the coffee sector is facing many challenges ranging from low productivity and high production costs to the threat of climate change, we are curious to see the multitude of initiatives that have coffee recycling as their main theme.
It is estimated that 152.1 million bags of coffee were consumed worldwide in 2016 and in addition to the known properties of its residues as natural fertilizers, many initiatives are seeing this resource as a suitable raw material for new industrial projects, food or artistic.
TURNING THE REMAINS OF COFFEE INTO FERTILIZER FOR THE GARDEN OR THE ORCHARD
It is important to know that coffee fertilizer is only indicated for acidophilic plants, or those that require an acid soil for optimal development. This is the case of roses, blueberries, strawberries, azaleas, hydrangeas or rhododendrons, for which coffee provides important potassium, magnesium and nitrogen content, essential nutrients for the healthy growth of these plants.
To prepare this organic compost you will only need the discarded coffee beans as raw material, some newspaper sheets and a tray as instruments. When you have everything ready, arrange the paper on the source and spread the coffee beans so that they dry more easily when you place them in the sun. After a few hours have passed, place the coffee in a jar and beat it with a fork to break up any caking for a uniform powdery compost.
When you have your coffee compost ready, you just have to pour it around the root of the plant, and stir the soil so that the compost adheres better to the soil substrates. Likewise, this is much more effective if you prepare the soil in all your pots and beds for acidophilic plants with this coffee fertilizer before growing the plant, in order to provide it with an enriched soil that stimulates its growth.
ARTISTIC REUSE OF COFFEE GROUNDS
One of the most recent that we have known could be seen at the "Object Rotterdam" fair. In the latest edition of this curious meeting, which is held inside an old ship and aims to give a second life to objects that seemed condemned to oblivion, the work of the designer Mayra Sérgio was observed. His performance consisted of mixing the ground grain - which he accumulated in a small mountain - with hot water. The mixture, after going through a machine that gave it shape, became a brick with which this Brazilian sought to build a “sensorial refuge”. The installation of this young Brazilian is part of an investigation on elements that give people a “sense of belonging”. For her, food has a highly evocative power that makes it possible to feel 'at home' through the physical ritual of preparing it: the look, smell and taste. "It has the power to momentarily transform itself into architecture, to protect our bodies through our senses." His personal story - he was born in Brazil and lives in Holland - made him consider how the spaces and objects that surrounded him interfered with that feeling and it was that idea that led him to choose coffee as his artistic material. His idea for the fair was to create this soaked refuge that "will take on a different appearance every day and eventually grow or fall." We have not been able to find out what the outcome was.
INDUSTRIAL REUSE FOR COFFEE RESIDUES
We have also recently learned of the practical utility that a Navarran company has found for coffee grounds. In a project carried out in collaboration with the Public University and the Government of Navarra, Biopar has managed to convert coffee grounds into fuel in the form of pellets for boilers and stoves. According to the information provided by the project, the characteristics of coffee give the 'pellets' of this material 20% more calorific value than wood pellets, they generate less ash and can be considered more ecological, since it is not necessary to cut any tree. The manufacturing process they have come up with has proven to be technically and economically feasible and their developers are confident that it allows them to compete with some of the more common ways of obtaining energy for these heating systems. The only thing that users should bear in mind is that it is necessary to make an adjustment in their appliances since the heat capacity of coffee pellets is greater than that of usual materials.
COFFEE GROUND COOKIES
Coffee residues have also been revealed as a possible ingredient for the production of bakery, pastry and confectionery products with significant associated benefits. Researchers from the Food Science Research Institute (CIAL) have carried out a study to verify the value of the use of coffee grounds as a food ingredient in biscuits and have concluded that they could be used as a sustainable natural source of dietary fiber, whose consumption could produce benefits for gastrointestinal health and prevention of diabetes or obesity.
As raw material, they used coffee grounds derived from the industrial production of instant coffee and the results they obtained indicate that these residues are a sustainable natural source of insoluble antioxidant dietary fiber and also of other components of nutritional interest, such as essential amino acids. or low glycemic carbohydrates. As recognized in the study, the application of coffee grounds in the production of cookies or other similar products is an opportunity to reuse this resource at a very low cost.
As we mentioned at the beginning, new possibilities are opened to reuse coffee grounds, beyond the traditional applications in biofuels, compost, feed, biosorbents, etc. And what do you do with the coffee grounds?