Ferments pulped beans, still coated in mucilage, sealed with little oxygen, then finishes them as a washed coffee.
Anaerobic washed coffee is fermented as pulped beans still coated in mucilage, in a sealed, low-oxygen environment, and then finished as a washed coffee. It shares the general anaerobic profile: a tendency toward lactic-acid fermentation, and a risk of unpleasant flavors if the wrong microorganisms take hold or practice is careless.
How it worksPulped beans, still enveloped in mucilage, ferment in a sealed, reduced-oxygen environment, and the coffee is then finished as a washed coffee.
Step by step
- 01
Cherry is pulped, leaving the mucilage on the beans.
- 02
The beans ferment in a sealed, reduced-oxygen tank or bag.
- 03
The coffee is washed and dried as a washed lot.
Our notes on Anaerobic Washed are still being checked against their sources, so for now this page shows only the facts we can stand behind.
What can go wrong
- As with other anaerobic methods, wrong microorganisms or careless practices can give unpleasant flavors.
A variant of
At the same stage
Sources · 2 Every sentence here was checked against a source we read. Taste notes are what guides describe, not promises about your bag. Last revised 2026-09-30. Some details here are less settled than others.
- Coffee Report: Anaerobic Fermentation and Other Processing Experiments · Coffee Review
- Coffee basics: A guide to anaerobic fermentation · Mtpak Coffee