decaf

The CO2 process of decaffeination uses liquid Carbon Dioxide (CO2), a highly selective solvent for caffeine. The green coffee is soaked in water to open the bean’s “pores”, beginning the decaffeination process whereby caffeine molecules are able to move in and out of the beans. The coffee is then placed into a compression tower, where it is brought into contact with pressurized liquid CO2. The pressure transforms the CO2 into a supercritical state, where it is part liquid and part gas. By circulation through the coffee, the carbon dioxide bonds with the caffeine, drawing it out from the beans. The CO2 is then separated into an evaporator, where the caffeine precipitates from the CO2, which means the caffeine can be collected and used to resell. After this, the CO2 is pumped back into the vessel containing the green coffee for a new cycle. When the required caffeine level is reached, the CO2 circulation is stopped and the coffee is discharged into a drier where it is gently dried until it reaches the original moisture content. The coffee is then ready for roasting.