How to Decaffeinate Coffee
Swiss Water Process
In the Swiss Water Process, the green coffee beans are soaked in hot water to remove the caffeine and compounds responsible for much of the flavor of the coffee flavor. The first batch of coffee beans is then discarded, while the caffeine is stripped from the solution by means of activated carbon filters. This leaves a solution saturated with flavor compounds, which is then used to soak a new batch of decaffeinated green coffee beans. The principle of water procesed decaf coffee is that the solution is saturated with all components soluble in water other than caffeine. Therefore, only the caffeine in the bean is allowed to escape whereas the rest of the compounds are in equilibrium. Unfortunately, the flavor of batches is intermixed since the chemically saturated solution is used repeatedly.
In the carbon dioxide decaffeination process, green coffee beans are soaked in highly compressed CO2, which extracts the caffeine. The caffeine is then removed from the CO2 using activated carbon filters, which are then reused to extract caffeine from the coffee again.
Sparkling Water Process
The sparkling water decaffeination process is similar to the CO2 method, but instead of removing the caffeine with activated carbon filters, the caffeine is washed from the CO2 with sparkling water in a secondary tank, which is then recycled to extract more caffeine from the coffee. The solvent consists of approximately 99.7% compressed carbon dioxide and 0.3% water.