Natural decaffeination process by Swiss Water Process
Swiss Water Process is a natural decaffeination process of coffee that was developed in the 1970s by a Swiss company. This process works by osmosis and by the solubility of coffee beans. Only water is used for decaffeination to remove the caffeine from the coffee. In the first step, a batch of green coffee is soaked in a tank of hot water. The water extracts the caffeine molecules from the coffee, as well as all the good aroma oils and other soluble components. The water then flows through a special carbon filter that is so fine that it captures only the caffeine molecules. What remains is a flavorful, caffeine-free liquid that contains only the aroma oils and other soluble aroma components of the coffee bean. A batch of tasteless, decaffeinated coffee beans also remains, but it is useless and must be disposed of. With the flavorful and decaffeinated liquid, called Green Coffee Extract (GCE), the actual decaffeination can now begin.
The second step is to soak a fresh batch of green coffee with the GCE. As we learned earlier, this liquid is already fully saturated with coffee solubles (oils and other aroma molecules) and therefore no longer dissolves flavors from the green coffee, only caffeine molecules. The GCE binds the caffeine from the beans. Now the liquid is filtered through the carbon filter until all the caffeine has been absorbed from the water. This process is repeated until the coffee beans are 99.9% caffeine-free. The entire process takes 8 to 10 hours. No chemicals are used, which makes this decaffeination process particularly natural and gentle. However, there is a small downside, because a lot of water is needed for this process, which is why this method is not one of the most sustainable.