Ethiopia Guji Hambela Carbonic Maceration

Deri Kidame Washing Station is composed of 181 drying beds and dozens fermentation tanks for both Anaerobic and Carbonic Maceration processes. While mostly naturals are produced due to the heavy demand for this process and the suitability of the cherries, we are planning to do more fermentations.

Harvest, Post-Harvest:
Kenzu Ahmed is the Station Manager for Deri Kidame Station. The station owned by Tracon Trading is named after the district “Deri Kidame” located in the Wamena district of Hambela. Kenzu has been working in the Hambela area for 3 years now and has been sourcing his coffees very carefully. He only chooses farmers and red cherry suppliers who bring high quality cherry from experience.

Our in-country partner has been experimenting with new processing methods as a way to increase value and stand out among a growing number of specialty washing stations in Ethiopia. They have been trialing anaerobic fermentation with several of their washing stations in Yirgacheffe since 2015. Uraga washing station receives cherries from farmers in the surrounding region. The station is located in Guji, a coffee growing region that was once part of Yirgacheffe but whose microclimate produces such unique coffee, that it was allocated as its own coffee growing region. Farming methods in the region remain largely traditional. Guji farmers typically intercrop their coffee plants with other food crops. This method is common among smallholders because it maximizes land use and provides food for their families. In addition to remaining traditionally intercropped, most farms are also organic-by-default. Farmers in Guji typically use very few—if any—fertilizers or pesticides.

Most farm work is done manually by the immediate family.
To capitalize on the magnificent climate, Uraga washing station provides training to help farmers produce better quality cherries. Training focuses on procedures for harvesting and transporting cherries. While Ethiopia is famous as coffee’s birthplace, today it remains a specialty coffee industry darling for its incredible variety of flavors. While full traceability has been difficult in recent history, new regulations have made direct purchasing possible. We’re partnering directly with farmers to help them produce top quality specialty lots that are now completely traceable, adding value for farmers and roasters alike. The exceptional quality of Ethiopian coffee is due to a combination of factors. The genetic diversity of coffee varieties means that we find a diversity of flavor, even between (or within) farms with similar growing conditions and processing. In addition to varieties, processing methods also contribute to end quality. The final key ingredients for excellent coffee in Ethiopia are the producing traditions that have created the genetic diversity, processing infrastructure, and great coffee we enjoy today. Most producers in Ethiopia are smallholders, and the majority continue to cultivate coffee using traditional methods. As a result, most coffee is grown without chemical fertilizer or pesticide use. Coffee is almost entirely cultivated, harvested, and dried using manual systems.

After careful selection, the coffee cherries are placed in plastic bins to undergo a 96-hour fermentation process. This begins with the injection of CO2, which displaces the oxygen in the bins and creates a controlled, anaerobic environment that’s ideal for carbonic maceration. This environment initiates a series of enzymatic reactions, resulting in a transformation of the mucilage covering each coffee bean. Over time, this mucilage changes in color, developing intense pink and dark hues, which are then absorbed by the parchment layer. This color transformation signals a shift in the coffee’s chemical composition, ultimately enhancing its sweetness, body, and the fruit-forward notes that make it distinctive.

Following this initial phase, the coffee is pulped, removing the outer cherry skin, and the beans are returned to the bins with their own sugar-rich juice. This juice amplifies the fermentation, as naturally occurring microorganisms now begin to actively metabolize the sugar chains in the mucilage. This stage, also anaerobic, is essential for developing the coffee’s fragrant and acidic qualities, contributing to its aromatic complexity. During this period, CO2 is periodically injected to maintain the oxygen-free environment and ensure the continued maceration effect.

In total, the coffee undergoes 96 hours of fermentation, split between the cherry and mucilage stages, before moving to an 18-22 day drying period. This extended process yields coffee with enhanced depth, fruitiness, and aromatic complexity, characteristics highly valued by specialty coffee producers and enthusiasts alike.

Guji is a zone in South-Eastern Oromia. Due to mining activity, it was illegal to travel to parts of the Guji zone for some time in the past, making this a newer region to producing coffee. As the land has been an untouched forest for quite some time, the soil is perfectly fertile, leading to excellent coffee being produced.