A decaffeination method where beans are placed in a liquid bath of highly-pressurized CO2. Supercritical CO2 acts as the solvent penetrating the coffee and extracting the caffeine, so when the coffee returns to normal temperature and pressure, there is no residue once the CO2 floats away. Some C02’s approach the chemical decafs in cup quality; others are nearer to SWP decafs. Here’s a longer and perhaps simpler explanation: Here is how it works: Coffee is mixed with water, and the beans expand in size, their pores get opened and the caffeine molecules become mobile. At this point carbon dioxide is added at 100 atmospheres pressure to the pure water. Basically the water and the carbon dioxide are mixed to create the sparkling water. The carbon dioxide acts like a magnet and attracts all the caffeine molecules that became movable. When the caffeine is captured by the carbon dioxide, this is removed. The carbon dioxide is very selective and it doesn’t touch the carbohydrates and proteins of the coffee beans, which would damage quality. When the carbon dioxide has finished removing the caffeine, the coffee seeds are dried naturally. Carbon dioxide is then recycled and caffeine is sold for other commercial uses. See Decaffeinated Coffee.