What is Washed Processing
Written by Allana Kennedy, Roaster at Outpost Coffee Roasters
At Outpost Coffee Roasters we have descriptions on our bags of coffee of what process was used to dry and remove the coffee seed from the coffee cherry. You may have seen the description of Washed, Honey and Natural processes, and wondered what this meant. Below, I'll explain the washed process and its impact on taste.
Washed processed coffee lets you really taste the bean alone, without any of the fruit that surrounds it interfering with the flavour.
In the Washed method the coffee cherry is removed mechanically (by a 'depulper') and the seed is washed of all the mucilage. For coffee, Washing means that the seeds are put into fermentation tanks to break down the sugars and strip the mucilage away.
What does this taste like?
- Washed coffees tend to be the most clean tasting coffee and rely on the bean to be perfectly farmed as you can not hide the bean flavour in the sweetness from the outside cherry.
A farm's terroir, the varietal, the picking, fermentation, and drying all have to be exceptional. This is why so many specialty coffees are washed, as the true taste of a single origin bean is highlighted like no other process.
On a recent trip to Finca San Ramon coffee farm in Nicaragua, I was able to watch how the processing happened step by step.
- First the pickers came down from the mountains and dropped off their bag of cherries. They then wait in line and the farm manager will get them to fill a bucket which is then thrown into a pit that channels down into the pulping machine below. The pulping machine has blades that spin around and cut the cherry away from the bean. Once a cherry has been cut/pulped, the outer cherry is whisked away to be composted and used as fertilizer. The bean is spun through a screen that allows only denser beans that are a certain size to fit through. Beans that are the perfect size and heaviness are then moved along into the washing station.
Fermentation is when sugars and starches are broken down and become acids or alcohol.
Fermentation is the interaction after the cherries have been pulped and the beans are covered in water. Water will help to extend fermentation time and will result in a softer body, complex acidity, and more refined flavour profile.
Fermentation times and temperatures vary and depend on the seed itself and the climate in which the seed is being processed and can be anywhere from 12 hours to 6 days.
Hope this article helps in anyway and you can understand the processing a little better. Next time you make a coffee with a washed process see if you can taste the difference!