We all know what decaf is and you’ve probably experienced the blander, less potent coffee cousin, but taking time to stop and ponder the possibility only brings more questions. In fact, how the caffeine is removed from coffee beans is the most common question we get from individuals and groups touring the Roaster.
Once you get past the “Why?” (Why, why would anyone prefer decaf to the real McCoy?), you move on to the more perplexing issue of how that pesky caffeine is actually removed from the poor, unsuspecting bean.
photo credit: Mykl Roventine
So here’s the basics of “Decaffing the Bean”.
The Direct Solvent Process is probably the most common and starts with steaming the green coffee beans so that they swell and the waxy coating is dissolved. The beans are then rinsed extensively (up to 12 hours!) with a methylene chloride or ethyl acetate (allegedly harmless to humans) solvent, which bonds to the caffeine. The solvent (and now caffeine too) are removed and the beans are steamed again to remove any residuals – the solvent evaporates and caffeine with it! The non-caffeine components and flavor compounds are reabsorbed into the beans with yet another, you guessed it, soaking! Any trace amounts of solvent burn off when roasted.
The Indirect Solvent Process is very similar to the Direct method except that water is used versus steam and caffeine is removed from the water rather than the beans – using the same types of solvent. This technique is also known as “Water Processed” – chemicals are still used but never come in direct contact with the beans.
Other variations utilize Swiss Water and Carbon Dioxide processes but these are not as widely used. The Direct Process is thought to result in least amount of flavor loss.
There it is! Not quite so magical but makes a lot more sense. The great news is that caffeine has nothing to do with the flavor loss of the decaf process. Methods of caffeine removal and decaf brewing are improving all the time so if you’re a decaf addict, shun the oxymoron and be diligent about the search for the best decaf brew – and share it when you find it!
