Coffee Processing Method
Carbonic Maceration
Borrowed from Beaujolais winemaking, carbonic maceration ferments whole, intact cherries in tanks flushed with carbon dioxide. Without oxygen, fermentation begins inside each cherry — intracellularly — converting sugars and malic acid before any microbe touches the seed. The technique came to prominence when Sasa Sestic used a carbonic-macerated coffee to win the 2015 World Barista Championship.
The method gives processors unusual control over cup direction: cooler, shorter macerations preserve florals and elegance, while warmer, longer ones build winey, jammy intensity. It has become a signature offering of ambitious mills in Colombia, Panama, and Australia-influenced processing programs across Asia.
How the carbonic maceration works
- Whole intact cherries sealed in tanks
- Tank flushed with CO₂ to purge oxygen
- Intracellular fermentation 24–96 hours, temperature-controlled
- Cherries removed, then dried whole or pulped first
- Extended slow drying
Carbonic Maceration at a glance
| Flavor impact | Winey, jammy fruit, banana and bubble-gum esters, silky body; florals preserved in cool macerations. |
|---|---|
| Key risks | Requires gas handling and strict sanitation; expensive failures if temperature drifts. |
| Water use | Minimal during maceration; finishing method determines total. |
| Drying time | 15–30 days for whole-cherry finishes. |
Origins known for carbonic maceration
Carbonic Maceration — frequently asked questions
Who invented carbonic maceration for coffee?
The technique was adapted from wine by barista-producer collaborations in the mid-2010s, most famously by 2015 World Barista Champion Sasa Sestic and partner farms in Colombia. It has since spread through the competition-coffee world.
Does carbonic maceration taste artificial?
The ester-driven notes (banana, bubble gum, red wine) are natural fermentation products, not additives. Reputable producers achieve them purely through temperature, time, and CO₂ control — ask for process logs when buying.
Is carbonic maceration suitable for large commercial lots?
Rarely. Tank capacity, gas cost, and drying space keep most CM lots under a few tonnes. It's a micro-lot technique for competition and premium retail programs rather than container-volume trade.
Volcana Coffee produces washed, natural, and honey-processed lots on the Bolaven Plateau, Laos, with controlled fermentation and SGS-verified quality. Ask for our current processing menu and cupping samples.
Request a SampleOther processing methods
Washed Process
Clean, articulate cups with bright acidity and clear varietal character.
Natural Process
Heavy body, intense berry and tropical fruit, lower perceived acidity, wine-like sweetness. Signature profile of Ethiopian and Brazilian naturals..
Honey Process
Rounder body and more sweetness than washed, cleaner than natural.
Anaerobic Fermentation
Amplified sweetness and exotic notes — cinnamon, red wine, tropical punch.