# Co-fermented coffee, and how to brew it well

> Fermenting coffee cherries alongside fruit, flowers or spices is one of specialty coffee's more genuinely interesting recent developments.

By Joey Krosch. Published 2024-10-28, updated 2026-08-17.

Co-fermentation is a genuinely interesting recent development in
specialty coffee processing, and it's more than a novelty: producers
ferment coffee cherries alongside carefully chosen ingredients, tropical
fruit, flowers, spices, deliberately shaping the flavour that develops
during fermentation rather than leaving it entirely to chance.

## How it actually works

Three things happen during co-fermentation that don't happen in
conventional processing. The added ingredients contribute extra sugars
that change how vigorously fermentation proceeds. They also introduce
different microorganisms into the mix, broadening the yeast and bacteria
present beyond what naturally occurs on the cherry alone. And genuinely
new chemical reactions take place between compounds from the coffee and
compounds from whatever's been added alongside it.

Producers typically run this over 36 to 72 hours, carefully managing pH
and temperature throughout, this isn't a casual process, it demands real
attention to avoid an unpleasant, over-fermented result.

> **Why this matters to a home brewer:**
> Co-fermented coffees genuinely taste different from conventionally
> processed beans from the same origin, often with more pronounced,
> unusual tasting notes. Brewing them exactly like a standard coffee tends
> to undersell what makes them distinctive.

## Brewing adjustments worth making

Co-fermented coffees tend to reward brewing slightly gentler than usual:

- **Slightly lower temperature**, roughly 2°C to 5°C below your normal
  brew temperature, in the 88°C to 91°C range
- **A slower pour**, easing off your usual pour rate for pour-over methods
- **A touch coarser grind** than you'd use for the same origin
  conventionally processed
- **A longer bloom**, giving the more complex fermentation compounds time
  to properly hydrate before the main extraction

## What to expect in the cup

Co-fermented coffees are generally more complex than their conventionally
processed counterparts from the same farm, carrying more distinct tasting
notes and, often, a noticeably different character depending on what they
were fermented alongside. That complexity is exactly the point, and it's
part of why these coffees tend to command a premium: the process is
genuinely more involved than standard washed or natural processing.

## The takeaway

Co-fermentation isn't a gimmick, it's a real, deliberate processing
technique that changes what ends up in the cup in a way you can taste.
If you come across one, brewing it slightly gentler than usual, cooler
water, a touch coarser, a bit more patience on the bloom, is the best way
to actually let that complexity show rather than muting it with a
standard brew.