Decaffeination: The Roselius and Swiss Water Processes
Roselius process
The first commercially successful decaffeination process was invented by Ludwig Roselius and Karl Wimmer in 1903. It involved steaming coffee beans with a brine (salt water) solution and then using benzene as a solvent to remove the caffeine. Coffee decaffeinated this way was sold as Kaffee HAG after the company name Kaffee Handels-Aktien-Gesellschaft (Coffee Trading Company) in most of Europe, as Café Sanka in France and later as Sanka brand coffee in the U.S. Café HAG and Sanka are now worldwide brands of Kraft Foods. Due to health concerns regarding benzene, this process is no longer used commercially and Coffee Hag and Sanka are produced using a different process.
Swiss Water Process
The Swiss Water Process is a method of decaffeinating coffee beans developed by the Swiss Water Decaffeinated Coffee Company. To decaffeinate the coffee bean by the Swiss Water method, a batch of green (unroasted) beans is soaked in hot water, releasing caffeine. When all the caffeine and coffee solids are released into the water, the beans are discarded. The water then passes through a carbon filter that traps caffeine but lets the coffee solids pass through. The resulting solution, called “green coffee extract (GCE)” by the company, is now available for decaffeinating coffee. New green coffee beans are introduced to the GCE. Since the GCE is coffee solids without caffeine only the caffeine diffuses from the new beans. The GCE passes through proprietary carbon which captures the caffeine. The process repeats, filtering out all the caffeine until the beans are 99.9% caffeine-free. These beans are removed and dried, and thus retain most if not all of their flavor.
Although the process was pioneered in Switzerland in the 1930s, today the world’s last major Swiss Water Process decaffeination facility is based near Vancouver, British Columbia, Canada. However this process is simple enough to be used locally by many coffee roasters.
