Coffee Processing

Coffee farming is tough work. But working to grow coffee from seed to harvest is only part of the job. Once the coffee is harvested, the real work starts: Processing.

Processing coffee is the act of removing the layers of skin, pulp, mucilage, and parchment that surrounds the coffee bean, the raw ingredient that the farmer will sell. How a grower chooses to process the coffee will have a profound impact on how that coffee tastes.  

Given that we are currently offering coffees that have gone through several different processing techniques, we thought it might be a good time to go over what these techniques are and how they affect the flavor of the coffee. While there are several ways to process coffee, with countless variations of each, I will stick with the main ones we usually carry plus a few interesting twists on traditional methods that we have in stock.

Washed: Most of the coffee we sell is “washed” or wet-processed. For this process, the freshly-harvested coffee cherries are de-pulped which removes the skin and most of the pulp around the bean. The coffee then is placed in tanks were it is allowed to naturally ferment fro 18-24 hours. This fermentation works to remove mucilage which is a sugary, slimy substance that surrounds the bean. Once the growers determines that the coffee has had enough fermentation the coffee is washed with fresh water which stops the fermentation process. Then the coffee is dried before resting for 60-90 days. Coffees that are washed tend to be floral and more citrus-y.

Our new Guatemala Maragogype is washed.  

Natural: the second most common process that we carry is natural or dry-processed. Here, ripe cherries are laid out on a patio or on Kenyan beds, fruit intact, and the coffee is allowed to slowly dry. Once dry, the fruit is stripped away from the bean. Coffees that are dry-processed tend to be more fruity and can be very intense and berry-like.

Our Ethiopia Gedeo is a good example of a classic, naturally-processed coffee.

A variation on the Natural Process is called Wine-Processed. In short, instead of harvesting the cherries at the peak of harvest, the cherries are allowed to over-ripen on the shrub, thus giving the cherries a higher concentration of sugar.

The coffee we have right now from Duncan Estate is Wine-processed.

Honeyed: This process has grown in popularity over the last few years, especially in countries like Costa Rica and El Salvador. For Honeyed coffee, the harvested cherries are de-pulped, then the coffee is immediately placed on beds for slow drying – bits of pulp/fruit actually dries on to the coffee. Coffee processed in this way, tends to be fruity like a natural and a little more creamy in mouthfeel than a washed coffee.

Fincal Loma La Gloria’s Fancisco’s Pacamara is made up of mostly honeyed coffee.

Variations on a theme:

ETHIOPIA-style: 48 hour UNDER WATER fermentation, washing every 12 hours...which just means we add a little bit of fresh water, take a little out and turn with a wooden paddle, wash the parchment then it goes back to fermentation tank to soak in fresh water for 24 hours and then placed on drying beds. The main difference between regular washed and the Ethiopia method is that the fermentation time is very long and occurs when the coffee is covered in water – key is the coffee water must be changed frequently to avoid off-flavors in the coffee.

Burundi-style: 24 hour DRY fermentation, washing every 12 hours...which just means we add a little bit of fresh water and turn with a wooden paddle, then 24 hour UNDER WATER fermentation, washing again every 12 hours then wash the parchment then it goes back to fermentation tank to soak in fresh water for 24 hours and then placed on drying beds. While the initial 24 hour fermentation time is average for most washed coffee, here the coffee is washed mid-way through the process and THEN the coffee undergoes continued fermention under water.