Coffee relies on water, in growing, processing, and the final extraction into our cup. You can’t have coffee without water somewhere along the line. As specialty coffee baristas and enthusiasts, we carefully control the quality of water that we use at work with complex reverse osmosis systems and mineralising cartridges, and at home with really good filters on our taps or in the form of a filtered water jug.
Then there’s the water that we don’t often think of: the water used in the processing of coffee. Coffee is processed in three main ways: 1. washing 2. natural processing 3. honey processing. All of these require water whether it be to clean dirt and debris from the cherries or for fermenting the beans during the washing process.
The washing process uses water in a fermentation process or in a mechanical de-pulping, often both. This wet processing uses about 10,000m3 of water per 1 ton of green coffee. This water becomes contaminated and polluted with the pulp. Subsequently the impact on water used in the processing of coffee can have a pollution load of 30 to 40 times higher than that of urban sewage!
When I travelled to Kenya (one of the biggest coffee producing countries in the world), I noticed two things: everything was green and tropical, and there was not a vast amount of fresh, running water that would be considered clean enough for specialty coffee processing. This provides great growing conditions but not the best of conditions for processing coffee. This lack of good water tells us that when we receive a phenomenal washed coffee, especially from Africa, we know that it must be good as someone has taken the time and precious resources to wash this coffee giving us the beautiful clean, bright, citrus flavours so common in washed coffees. A good example of this is our Ethiopian Guji and Kolowa, both from the Oromia region of Ethiopia, despite these areas experiencing a horrific drought.
In recent years the trend has been to conserve water in the washing process by using more efficient machines and methods, such as shorter fermentation in water troughs followed by removing the mucilage in water efficient machines. But the real issue is that this water has to go somewhere… it can be recycled once or twice until the quality of water is unacceptable for high grade coffee. Often the water is released into nearby waterways causing the nutrient level to rise. Resulting in possible eutrophication of the water, leading to massive algal blooms and deaths of aquatic animals. The best use of this water is in fact of irrigation of crops be it for coffee or others.
The changes are happening though; more and more wet milling stations are adopting water wise technologies and taking an active role in the correct disposal of their water. This will, however, come down to the cost to the mill owner as well as the strictness of local legislation and an informed coffee buyer who is not willing to buy coffee that is polluting the local area. Local farmers shouldn’t be encouraged to produce the best coffee at the cost of the environment or the social well-being of the people living in that area. And as coffee rosters we need to be very aware of how the coffee we roast is being farmed and processed and the impacts that it has on the area.
When we sip on our coffee let us remember just how much of an important role water plays in the life cycle of coffee. The future of human kind will undoubtedly be influenced by water, so will our coffee.
– Matt –