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The Swiss Water Process (SWP) is a non-solvent method for decaffeinating unroasted coffee beans. It was introduced by Coffex in 1979,[1] and was, at that time, the only commercial decaffeination method that did not use solvents. The Swiss Water Process has quickly become one of the most popular methods of decaffeinating specialty coffee.[2] It is not so called because the water itself is Swiss, but instead because the process was developed in Switzerland.


The process proper[]

In this process, the coffee beans are soaked in caffeine-free green coffee extract, allowing the caffeine to be extracted from the bean and into the solution while the flavor components are retained in the beans.  The now caffeine-saturated green coffee extract is then processed through activated charcoal to remove the caffeine, thus becoming caffeine-free again and ready to extract caffeine from a new batch of coffee. The coffee beans are then dried to their originating moisture level and re-bagged. The Swiss Water Process results in coffee that is 99.9% caffeine free.[3]

No usable By-products[]

In other methods of decaffeination, the caffeine is recovered from the mixture and sold separately from the coffee.  Typically, caffeine is caputured through the introduction of a volatile solvent (such as methylene chloride or ethyl acetate), which allows the caffeine to attach to the solvent and then be recovered through dehydration.  However, in the Swiss Water Process, no chemical solvents are used. The cost of this process is usually slightly higher than solvent-based processes.[4]


One criticism of this process of decaffeinating coffee beans is that different batches of coffee are processed in the same solution, resulting in a less distinctive flavor for each origin. Often, the liquid extracted from one batch of coffee beans is mixed with the liquid from another batch. The result being that the decaffeinated liquid returned to that first batch will still contain oils and flavors from the other batch. This practice will blend the flavors of the coffees, muting the more subtle notes of each batch.[5]

See also[]


  1. Anthony Wild (2005). Coffee: A Dark History, 210. ISBN 0393060713.
  2. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 76-77. ISBN 0312246668.
  3. Marie Nadine Antol (2002). “From Crop to Cup”, Confessions of a Coffee Bean: The Complete Guide to Coffee Cuisine, 37. ISBN 0757000207.
  4. Kenneth Davids (2001). Coffee: A Guide to Buying, Brewing & Enjoying, Fifth Edition, 232. ISBN 031224665X.
  5. Kenneth Davids (2001). Espresso: Ultimate Coffee, Second Edition, 76-77. ISBN 0312246668.