A speciality coffee flavour note across London.
Fermented notes in speciality coffee present as a tangy, winey, or slightly sour quality, sometimes recalling kombucha, overripe fruit, or natural wine. The sensation sits somewhere between sharp acidity and a pleasant earthiness, and in well-controlled examples it adds complexity rather than suggesting a flaw. This character develops when sugars and mucilage around the coffee seed undergo microbial activity during processing, and it can be amplified by longer fermentation windows or naturally warm climates in the producing region.
Coffees from Ethiopia, particularly those processed using the natural or wet-hulled methods, typically carry some degree of fermented character, as do many lots from Yemen and certain regions of Sumatra. Natural-processed coffees from Brazil and Central America will often show this note too, especially where extended cherry drying times are used. Anaerobic processing, in which the coffee ferments in sealed, oxygen-free vessels, has become closely associated with pronounced fermented flavours regardless of origin.
On a bag or menu, look for descriptors such as natural process, anaerobic, wet-hulled, or extended fermentation, as these are reliable indicators that fermented notes may be present. Words like winey, funky, or stone fruit in the tasting notes often signal a similar quality. Brew methods that preserve the full body of a coffee, such as French press or stovetop moka pot, tend to make fermented character more apparent, while filter methods like pour-over can highlight its interplay with brightness and sweetness.
Take our 60-second flavour quiz and discover roasts across London that are aligned with your palate — including ones carrying fermented notes.