The Basics of Fermented Coffee

Fermentation might sound fancy, or even unfamiliar when it comes to coffee. But it’s basically nature doing its thing. And the results can be magic. When microorganisms interact with the sugars in the coffee cherry, they create all sorts of flavor notes, from bright tropical fruit to rich chocolate. 

Coffee fermentation
This process initially started with washed fermentation, where beans sit in water tanks, and natural fermentation, where whole cherries dry in the sun. Then during the honey process, when some sticky mucilage stays on the bean, fermentation takes place
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Now, producers are getting more and more creative. Anaerobic fermentation (no oxygen) happens in sealed tanks, with or without particular microbes such as specific strains of yeast formulated just for coffee. It can produce intense complex winey profiles. Aerobic fermentation occurs in tanks but this time exposed to oxygen for a specified time period. Carbonic maceration started in winemaking, where grapes ferment in a CO₂-rich tank to create bright, candy-like flavors. Coffee producers now use this method too, giving the cup a smooth, fruity sweetness with playful notes like tropical fruit or bubblegum. Another more recent experiment is co-fermentation where beans are fermented together with a wide variety of different fruits or spices creating wild and unexpected flavors. Some love the adventure, others stick to the classics—and that’s the beauty of coffee.

So, should you try fermented coffee? Absolutely. Whether it’s a mellow honey process, a funky natural, or a bold anaerobic, each cup tells a different story. And who knows—you might just find your next favorite brew in the process.