Kilimbi - Anoxic
The elevation of Kilimbi washing station lends itself incredibly well to the production of exceptional washed, honeys and naturals. Drying beds stretch across a large open plain, where airflow and sunlight have maximum exposure to the coffee as it dries. Built in 2016, it is the birthplace of Muraho Trading Company, as their first washing station.
Anoxic Process
Kilimbi is only accessible by boat, with farmers travelling across Lake Kivu to deliver their farm’s harvests. Its estimated annual production is approximately 33,300kg of milled green coffee, which is produced each harvest into volumes of honey, washed, and naturally processed coffees.
Once cherries are received, they are hand-picked and floated to ensure only those of the best quality continue to the processing stage. These cherries are placed into a deep cleaned fermentation tank. A sheet is then placed over the cherries, which is then submerged with cool water.
The seal created by the water pressing onto the sheeting creates a vacuum effect on the coffee below, creating an anoxic environment for fermentation to begin, which lasts for 48 hours. The water and sheet act as not only a sealant, but a heat exchange, allowing the heat build up to transfer to the water, which evaporates away. A stabilised temperature of around 25 degrees Celsius ensures that the cherry doesn’t over ferment. This temperature is regularly monitored, and if it falls too low for fermentation to continue, hot water is added to the water pillow, to provide warmth to the fermenting coffee underneath.
Once the fermentation is complete, the water is drained, and the sheet is removed. The now fermented coffee is rinsed and drained of all residual liquid.
To continue into the natural processing phase, coffee is dried in cherry on raised beds for between 4 to 5 weeks. The raised beds ensure optimum circulation of airflow, assisted by the cherry being turned every 30 minutes of the duration of its drying!
Region: Nyamasheke District.
Country: Rwanda.
Altitude: 1650 - 1650 MASL.
Variety: Red Bourbon.
Process: Anoxic Natural.