Characteristics of Double Anaerobic Fermentation in Coffee Beans - An Introduction to Double Fermentation Methods

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Introduction to FrontStreet Coffee's Colombian Paradise Estate Double Anaerobic Coffee

In recent years, anaerobic-fermented coffee beans have shone brightly on the WBC (World Barista Championship) final stage. In 2018, five of the top six competitors chose anaerobic-fermented beans as their "weapon" of choice.

That is why anaerobic fermentation is the most talked-about processing method in specialty coffee today.

Producer Diego Samuel entered a regional competition for the first time in 2015 and won first place. The coffee he grew received wider recognition, which motivated him to keep pursuing high quality. Today, Diego has developed innovative techniques applied not only on his own farm but also on the neighboring farms of family and friends, making him a promoter of science-based coffee cultivation in his area. Diego says he likes stepping out of his comfort zone because it pushes him to keep developing and improving, and he will continue competing — both to promote his work and to build new business relationships.

Anaerobic fermentation takes place in sealed stainless-steel containers, which don't carry over flavors from previous batches, so the resulting coffee tastes cleaner.

Because fermentation happens in a sealed environment, the various factors are easier to control: each processed batch is more consistent, and aromatic compounds are less likely to volatilize away.

With no oxygen present, the flavors come out rounder, often carrying cheese and cream aromas. Coffee processed this way typically has fuller body and wine-like aromatics.

In the "double anaerobic" method, ripe red cherries first undergo whole-fruit anaerobic fermentation in sealed containers for 24 hours. After the skins are removed, the beans ferment anaerobically for another 36 hours with the pulp still attached — hence the name. Throughout fermentation, Diego uses specific containers and monitors temperature continuously.

Coffee Information

Country: Colombia

Region: Cauca

Estate: Paradise Estate

Producer: Diego

Altitude: 2,050 meters

Variety: Bourbon

Processing Method: Double Anaerobic Washed

Flavor Notes: Peach, honey, floral notes, pineapple, mango, rum

FrontStreet Coffee Recommendation

Colombia is a playground for innovative processing, and the Paradise Estate double-anaerobic lot above is a prime example. For another take on anaerobic fermentation, FrontStreet's Finca Divisia (Dividing Line Estate) Sidra coffee is processed by anaerobic natural: sealed in pressurized stainless tanks with temperature, time, and pH precisely controlled, the beans develop extra tropical-fruit aromatics after oxygen-free fermentation.

Roasted medium-light, that Sidra delivers passion fruit, grape, apricot, and dried-fruit flavors with a juice-like texture — delicious as a pour-over, cold brew, drip bag, or even moka pot brew. The variety itself, Sidra, first appeared in Ecuador's Pichincha province and carries genetic markers similar to Ethiopian landraces, giving it an unusually floral, fruit-forward cup.

If you'd rather stick with tradition, FrontStreet's washed Huila coffee shows Colombia's classic side: roasted medium-dark to highlight dark chocolate and nut sweetness with moderate oils and a rich, full body, it suits pour-over, French press, moka pot, and espresso alike.