Processes · 4 · 13 label claims checked
The four words on the bag
Swiss Water, sugarcane EA, CO₂ and Mountain Water cover basically every decaf you will meet in Europe. They taste differently, they are regulated differently, and some of what is printed next to them is not true.
| Process | Solvent | Removed | Claims that fail | In the cup |
|---|---|---|---|---|
| Swiss Water ProcessTrademarked · Swiss Water, CA | No solvent | 99.9% (supplier guarantee) | 1 of 3 | Trade consensus, not laboratory finding, is that it has the least impact on origin character. Typically clean, chocolate and caramel leaning, with some loss of the most volatile aromatics. |
| Sugarcane EAGeneric · Descafecol, CO | Ethyl acetate | minimum 97% | 2 of 4 | Balanced, chocolatey and sweet is well supported. A corpus analysis of UK EA decafs found caramel and chocolate dominating, with citrus in about a third. A faint sweet-fruity character has an actual mechanism behind it — ethyl acetate is itself a fruity-smelling ester. |
| CO₂ processGeneric · CR3, Germany | Carbon dioxide | 97–99% | 1 of 3 | Best in class for body, lipids and mouthfeel. Reported to fare less well on very bright light roasts, where Swiss Water gives more vivid acidity. |
| Mountain Water ProcessTrademarked · Descamex, MX | No solvent | above 97% (plant's own claim) | 2 of 3 | Roasters report tobacco, malt and caramel, with the honest caveat that this depends heavily on origin and roast profile. |
Swiss Water Process
A water-only process run at a single plant in British Columbia, using coffee extract already saturated with everything except caffeine. The best known name in decaf, and the most misunderstood — it is a company guarantee, not a certification.
Also sold as: Swiss Water · SWP · water process decaf
Sugarcane EA
Ethyl acetate fermented from sugarcane molasses, used as an extraction solvent in Colombia. The sweetest-cupping process and the one whose marketing is furthest from its chemistry.
Also sold as: EA · ethyl acetate · sugarcane process · natural process decaf · EA decaf
CO₂ process
Caffeine dissolved out under pressure by carbon dioxide above its critical point. The most selective process and the best for body and mouthfeel — and the most expensive to run, which is why you see so little of it.
Also sold as: CO2 · carbon dioxide process · supercritical CO2 · liquid CO2 · subcritical CO2
Mountain Water Process
A water process run in Veracruz using glacier-fed watershed water. Mechanically a close cousin of Swiss Water — and the process most often described with a number its own plant does not claim.
Also sold as: MWP · Mountain Water · agua de montaña
Does the process decide the cup?
Less than the bag implies
No published head-to-head sensory comparison of the four processes exists. Tendencies are real — EA cups sweeter, water processes finish longer — but the green coffee and the roast matter more than the process, and anyone telling you otherwise is quoting trade consensus, not a study.