The fourth iteration of our partnership series with JUNTO hails from Rwanda. It’s an extremely complex coffee full of sensory experiences that remind us of everything from grape candy to sour red skittles, to lighter notes sometimes like Green tea and lychee. This coffee represents some of the best and most unique of Rwandan experimental processing and truly fits the bill of “Something Wild’.
What is a Low O2 Natural – 32 hour low oxygen whole cherry fermentation? Let’s here it from the perspective of the producer and roaster!
With honey and natural processing slowly becoming more common in Rwanda, Emmanuel began experimenting with whole cherry fermentation techniques that could differentiate him within the specialty market. 2019 marked the first year that these coffees were ever exported, and we’ve purchased a small volume each season of our partnership. As we look towards the future, we hope to collaborate more with Emmanuel on his experimental processes and push towards the most precise and replicable methods possible.
This coffee underwent a simple cherry-holding stage prior to drying, whereas top quality cherries are tightly packed into sealed plastic ecotact bags. Here they are left to ferment, undisturbed and under shade for a set period of time. This specific lot was fermented like this for a period of 32 hours. In today’s specialty coffee vocabulary, this would likely be considered a form of anaerobic natural processing. However, because all fermentation is in fact considered to be anaerobic by definition, we like to refer to this more specifically as a low oxygen fermentation.
The goal here is to create a unique environment in which the cherries have very limited interaction with oxygen, but the environment is not 100% free of oxygen during the entire process. As fermentation takes place, carbon dioxide is released and progressively pushes oxygen out of the plastic bags. The particular environment created changes both the rate of fermentation and the specific yeast and bacteria present. In our personal sensory experience, we’ve found that the low oxygen whole cherry fermentations always promote high intensity and complexity of fruit flavors and sweetness in the coffee.
PROCESSING STATION: Akagera
LOCATION: Bushekeri Sector, Nyamasheke District, Western Province
HARVEST SEASON: April – June
STATION OWNER: Baho Coffee / Emmanuel Rusatira
EXPORTER: Baho Coffee / Emmanuel Rusatira
IMPORTER: Sundog Trading
ALTITUDE of FARMS: 1600 – 1900 masl
VARIETY: Red Bourbon
PROCESS: Low O2 Natural – 32 hour low oxygen whole cherry fermentation