Get ready for one of the most dynamic decaffeination processes yet! That is the carbon dioxide or C02 decaf method. What makes this method so incredible? Well, it’s a process that results in no waste, is natural, utilises no artificial chemicals or ingredients, and also applies tons of pressure to essentially crush the caffeine out of beans. Sounds pretty extreme! Let’s find out a bit more about this intense decaffeination process.
The story of C02 decaffeination goes back to 1967. It was then when a chemist at Max Planck Institute named Kurt Zosel stumbled upon an interesting discovery. Zosel, like many other chemists, was using high-pressure C02 to remove individual substances from other mixtures. This process leaves the remaining mixture more or less unchanged, save for the one removed substance. It was during one of these sessions with high-power C02 that Zosel noticed that a simple alkaline like caffeine just so happened to be banished when exposed to high-pressure C02. He tinkered with this concept and by 1970 had obtained a patent for his futuristic C02 decaffeination technique.
The method itself is as scientific and sophisticated as the man who developed it! First, the green coffee beans are soaked in water which allows them to swell up and become more optimal for caffeine extraction.
Next, the green beans are hurled into a stainless steel extraction vessel. The vessel is then sealed up. The C02 in its liquid form is then blasted into the beans at about 1000 pounds of pressure per square inch and at temperatures reaching up to 93 degrees Celsius. This high-pressure form is known as supercritical C02.
Now, the C02, acting as a solvent, begins to suck up some water but mostly the caffeine. All the beans will need some time, about 5 to 7 hours, to have all their caffeine expunged. The next step sees the beans removed from the sealable drums, dried, and roasted. The caffeine that was removed doesn’t get thrown away, either.
Instead, that remaining excess caffeine is recirculated and sold to companies that add caffeine to their products. The circle of caffeine is never broken! Just transferred around a bit.
The result for the green coffee beans, though, is a removal of about 97% or more of the caffeine. Some of the original naturally occurring compounds in the beans get expunged, though, and this can affect the taste. In some cases, C02 decaf can taste a bit too mild or too flat. But generally, C02 decaf beans are smoother, easier on the palate, and not overpowering.
The C02 method is a true work of scientific art. It is also a process that does not use any chemicals or artificial ingredients and is healthy for the environment. Your coffee beans, though exposed to some intense pressure, are no worse for wear, in fact, they are smoother, clear tasting, and best of all, decaffeinated!