What is washed processing?
In washed processing, the fruit flesh is removed right after harvest, the bean is fermented in water (12–48 hours), washed, and dried. The result: a clean, clear cup profile.
Why that is
Washed processing is the most elaborate and water-intensive of the three classic processing methods. But it also delivers the "cleanest" flavour profiles — the aromas of the bean itself come through unadulterated, without influence from the fruit flesh.
The process in four steps: first, the cherries are stripped of their fruit flesh within hours of harvest in a depulper (a mechanical depulping machine). Second, the beans with the still-attached mucilage layer enter fermentation tanks, where microorganisms break down the mucilage over 12–48 hours. Third, the beans are washed with clean water to remove all residue. Fourth, they dry on raised beds (African beds) or patios in the sun until they reach a moisture content of 10–12%.
Fermentation is the critical step. Too short, and the mucilage remains, which can make the coffee slimy and astringent. Too long, and unpleasant vinegar-like off-flavours develop. Experienced processors monitor temperature, pH, and duration meticulously.
In terms of flavour, washed processing yields coffees with pronounced acidity, floral notes, and a clear, transparent body. The coffee tastes "like itself" — variety and terroir come through unmasked. Classic examples: Colombian Huila (caramel, citrus), Kenyan AA (blackcurrant, tomato), washed Ethiopian Yirgacheffe (jasmine, bergamot).
In practice at Green Wall Coffee
At our café on Sophienstraße 27 in Berlin-Lichtenberg, there are washed and natural coffees, and the bag tells you which. When guests ask what "washed" means, I explain the difference with an example: a washed Ethiopian usually tastes floral and clear, a natural one more berry-like and sweet. Same origin, different process — completely different flavour.
Stop by Sophienstraße 27 in Berlin-Lichtenberg — Mon–Fri 8am–5pm, Sat 10am–5pm.
Further reading
Related questions:
- What is dry processing (natural)?
- What does honey process mean and what variants are there?
- What Is Anaerobic Fermentation in Coffee?
Also relevant:
- What Is a Coffee Cherry and Is It Edible? — Growing, Origin & Climate
- Why does Ethiopian coffee taste fruity and Brazilian coffee nutty? — Growing, Origin & Climate
All questions in this topic: Harvesting & Processing