What is Swiss Water decaf?
Swiss Water decaf is coffee decaffeinated with the Swiss Water Process, a method that uses water and activated carbon filters, not a chemical solvent, to draw the caffeine out of green coffee before it is roasted. Wikipedia dates the technique to Switzerland in 1933; it was commercialized in 1980, and the Swiss Water Decaffeinated Coffee Company of Burnaby, British Columbia, introduced it in 1988.
How the process works
The method depends on one trick: a liquid called green coffee extract. It is water that already holds everything soluble in green coffee except the caffeine.
- Green coffee is soaked in the extract. Because the extract is already full of the coffee's other soluble compounds but has no caffeine, mostly caffeine moves out of the beans and into the liquid.
- The extract runs through activated carbon filters, which catch the caffeine.
- The cleaned extract goes back to the beans and the cycle repeats.
Wikipedia puts the time at 8 to 10 hours to reach the target level of caffeine. The beans are then dried and roasted like any other coffee.
How much caffeine has to go? In the United States, the FDA standard for decaf is at least 97 percent removed. The EU standard is stricter, expressed as 99.9 percent caffeine-free by mass.
What it tastes like
A Swiss Water decaf tastes like the coffee it started as, roasted the way the roaster chose, with the caffeine gone. The method is built to leave the flavor compounds in the bean, which is why the extract is pre-loaded with them. The quality of the green coffee and the roast still decide most of what you taste, so a good decaf starts with a good coffee.
Roasters treat decaf as a coffee worth roasting at several levels. In Massachusetts, Jaho in Salem sells its Swiss Water decafs at three roast levels, from light-medium to dark, and Armeno in Northborough offers a Sumatra decaf in three roast levels.
Swiss Water vs other decaf methods
| Method | What removes the caffeine | Chemical solvent? |
|---|---|---|
| Swiss Water Process | Green coffee extract and activated carbon filters | No |
| Mountain Water Process | A similar water-based method, carried out in Mexico | No |
| Ethyl acetate (sugarcane) | Ethyl acetate, made in this method from fermented sugarcane | Yes |
| Methylene chloride | Dichloromethane, removed from the green coffee before roasting | Yes |
| CO2 process | Supercritical carbon dioxide, which dissolves caffeine but leaves flavor compounds in the bean | No, carbon dioxide only |
Descriptions follow Wikipedia's article on decaffeination and our glossary entries on Mountain Water and sugarcane decaf. The first commercial decaf, developed by Ludwig Roselius in 1903, used benzene; the solvents used today replaced it.
Massachusetts roasters that use Swiss Water
Four Massachusetts roasters we list name the Swiss Water Process for their decafs on their own pages, as we read them on September 27, 2026. Others sell decaf without naming a method, or use a different one. A listing does not mean a roaster is part of the club.
- Armeno, Northborough: every decaf it sells is Swiss Water, from a Fair Trade Sumatra Takengon to Ethiopian Mocha Decaf and a decaf of its House Blend.
- Jaho, Salem: Velvet Hour (dark), a medium decaf espresso blend and Unwritten (light-medium), and a dedicated decaf subscription.
- Indigo, Northampton: a long Swiss Water list, including the organic Fair Trade Cascadia Blend decaf in several roast levels, single origin decafs and decaf flavored coffees.
- Acoustic Java, Worcester: Peru Decaf, a certified organic medium roast.
Two more use water methods without naming Swiss Water. Barrington in Lee calls its Decaf Gold, Decaf Berkshire and Decaf French water process, and Atomic in Peabody describes its Daydream Decaf as a water-processed Brazil. Esselon in Hadley uses Mountain Water beans for part of its range.
Decaf drinkers are easy to forget. A roaster in Northborough or Salem that builds a real decaf list gets to keep doing it when decaf drinkers buy from them, and the money pays roasters in those towns. Why Massachusetts roasters matter.
Decaf in the club
In the plan builder, set the style to Decaf. Each box brings a 12 oz decaf from a different Massachusetts roaster, at $16.99 a bag like any roast. The method depends on the roaster that box, so it will not always be Swiss Water; the packing slip names the roaster so you can check. First bag free, you pay $7.99 shipping. See the decaf subscription.
Related terms and sources
- Decaf and half caf in the glossary
- Methylene chloride decaf
- Green coffee, the stage when decaf happens
Sources, read September 27, 2026: Wikipedia, Decaffeination (the Swiss Water Process, its dates and timing, the FDA and EU standards, the solvent and CO2 methods, Roselius). Roaster facts come from each roaster's own pages, summarized on their profiles.