“Koji or not-Koji”
— sounds like Shakespeare
We are super excited about our this release of El Vergel Estate owned by the Bayter Family. We had the pleasure of Elias Bayter and his mother Marta visiting our roastery earlier this year. We also met up with Shady, Elias’ older brother in Milan and had (quite) a few beers when we met up with them in London at the London Coffee Festival.
We had tried and heard a lot about their koji fermentation lots and all of them tasted amazing.
To give a bit more background on this: Koji fermentation was a collaborative effort between the Bayter Family, Christopher Feran and Kaapo Paavolainen (Finish Barista Champion 2021). Kaapo had seen some work that Christopher had done with Koji- early experiments to try and lessen the impact of lipid oxidation on green coffee. This began a collaboration that took place on three continents and spanned far past the current standard protocols of processing.
Koji (rice wine starter) is evenly spread and coated around cherries prior to natural processing, thereby influencing the active microbiome during the natural drying phase. In numerous producing countries, it has been found to provide a consistent positive taste profile.
But what if the coffee was already amazing without koji fermentation? How can we tell?
We chat with Elias almost on a daily base, which is when our interest to this ‘new’ (but also centuries old) type of fermentation hit. Because we had tasted some of the most incredible coffees from them that were not koji fermented, you may recall our intensely popular /002, the Natural Caturra that is peachy and juicy or the /011, processed by the Bayter brothers that will blow you off your socks. So will the koji do? Will it actually make those incredible coffees even better?
A concrete question came to mind: which is better, the amazing Natural Caturra on its own or this time with the Koji fermentation part added?
Benchmarking koji fermentation, side by side.
And so our exclusive A.M.O.C. x El Vergel lot came to life: koji or not koji — that almost sounds like Shakespeare —
You can now try for yourself: same farm, same cherries, same picking day, same roasting profile.
A World’s first koji benchmarking tasting set.
ABOUT KOJI PROCESSING
This quite new process looks in practice a lot like a traditional natural processed coffee produced by El Vergel. Koji, a fungus that grows on rice, has a long tradition in food production but next to none in coffee processing. This open-source fermentation method is dependant on temperature primarily, keeping the cherries between 25-30 degrees when sitting on the drying beds is critical. The idea of the fermentation with koji is that it breaks down polysaccharides and pectin as well as produce amino acids. This is done so by inoculating the whole cherries within a shallow vessel for 36 hours. This looks very much like a pre-fermentation on a natural processed coffee, and from there the cherries are sent off to the drying beds. Little is now known about the impact of this fermentation method, but it’s safe to say that much more will be written on Koji processed coffees. For a more in-depth read on Koji fermentation, and on how to do it yourself, reference Christopher’s blog, who is an amazing writer and storyteller.