What is the CO₂ decaffeination process?

The CO₂ process uses carbon dioxide in its supercritical state - where it behaves simultaneously like a liquid and a gas - as a highly selective solvent to extract caffeine from green coffee beans. At around 250–300 bar of pressure and 45°C, CO₂ molecules penetrate the bean's cellular structure and bind specifically to caffeine, leaving larger flavour compounds largely intact.

The caffeine-saturated CO₂ is then depressurised, the caffeine separates out, and the CO₂ is recycled. No chemical solvents, no residues - just pressure, temperature, and physics.

It's widely considered the most flavour-preserving decaffeination method available. The selectivity for caffeine over flavour compounds is genuine, not marketing. The capital investment required means it's used by relatively few producers, which is why CO₂ decaf sits at a price premium. For roasters building a premium decaf, the quality difference is worth it.