From Seed to Cup: Why Naturally-processed Coffee Can Lead to a More Sustainable Future

Coffee is delicious, but its production isn’t always great for the environment. Broadly, there are two main methods to process coffee—wet and dry. 

The wet—or washed— method is famous for the clarity of flavour it brings to the coffee bean. Here, the coffee cherry is picked from the tree and first put through a depulping process or machine, where the fruit layer is mechanically removed from the seed. The seeds are then passed through a washer to remove the mucilage (flesh) stuck over the bean and finally put ot rest in a water tank for a few hours. Through this process, the cherry skin and mucillage is “washed” off the coffee bean. Thus, only the natural flavours absorbed during the growing cycle of the bean are retained, which reflect the climate, terrain, soil, and farming practices employed to produce the coffee. This method ensures fewer defects, a higher and more consistent yield and has traditionally ensured a cleaner cup. Consequently, the wet method has been favoured by the coffee industry, especially the speciality industry for its ability to showcase some of the “true” characteristics of the coffee. 

However, while wet processing has been the industry standard for many years now, its environmental impact is significant. There is immense water wastage. On average, it costs 140 litres of water to brew a single cup (125 ml) of coffee. 

Thankfully, growers, roasters, and consumers are increasingly conscious of the environmental cost of production. Today, there is a push towards more sustainable farming practices. Thus, a bag of coffee from your local roaster now also has processing methods marked as “dry,” “natural,” and “sundried.” These processes eliminate the need to wash the coffee. The whole coffee cherry is picked and left to dry in the sun on raised beds or brick patios till they reach the optimal moisture level (min 10.5% to max 12.5%). Climatic factors such as temperature and humidity are also majorly considered before natural coffees are scheduled to be processed. Once harvested the coffee cherry is turned regularly to avoid mould, rotting, and fermentation. After this, the green coffee bean is mechanically separated from the fruit (and skin) and left to “rest” before it is finally hulled and shipped from the farm. Given the extensive period of time the seed spends in contact with the fruit, beans processed via this method can exhibit dynamic and intricate characteristics.

Reducing waste

Aside from the large volumes of water required in wet processing, the steps involved mean that all the other parts of the coffee cherry—skin, pulp water, mucilage, and parchment—are disposed off. This waste water contaminates other water bodies in the area, creating a nutrient imbalance that can be damaging for the dependent ecosystems. This coffee “waste,” however, need not be thrown out and can instead be recycled. By processing beans naturally, studies have shown that coffee pulp can serve as effective replacements to commercial cattle feed and has also proved to be an effective substrate for growing mushrooms.