Decaf coffee tends to be regarded as one of those eternal mysteries. If the coffee bean naturally contains caffeine, then how in the world is that caffeine extracted? We might speculate idly over this conundrum with friends, but the conversation invariably moves on to more important topics, like cellphones and vacation plans.
And still, the question often remains unsolved. So once and for all, let’s take a look at
how decaf coffee is actually made.
Three Methods for How Decaf Coffee Is Made
Actually, there are three methods by which our
coffee loses its precious caffeine: water processing, the direct solvent method, and carbon dioxide decaffeination. To decaffeinate coffee using water processing, a batch of beans is first moistened and soaked while still green. While in the water, the beans release their caffeine and much of their flavor properties. Then, the caffeine is removed from the water, yet the flavor properties remain.
When the beans are returned to the water, they can re-uptake their flavor properties. Some processes will remove the caffeine from the water, discard the first batch of beans, and introduce new beans. When fresh beans are introduced, the water is already fully saturated with flavor and the beans can only release their caffeine.
The Direct Solvent Method of Making Decaf Coffee
The direct solvent method uses more chemicals to decaffeinate coffee. In Europe, they use methylene chloride, while other areas prefer using either coffee oil or ethyl acetate. These chemicals can isolate and extract the caffeine from the beans, rendering them safe for those unable to drink caffeine. Methylene chloride is considered a workplace toxin by OSHA, but it never comes into contact with the coffee beans themselves. Rather, it is used to extract the caffeine from the water that’s been used to extract the
caffeine from the beans.
While ethyl acetate sounds like a big, bad chemical, it is an organic, naturally occurring substance that’s commonly found in fruits and vegetables. It is non-toxic and perfectly safe to use when making decaf coffee.
Carbon Dioxide Decaffeination
The final method, carbon dioxide decaffeination, is much like the direct solvent method, but uses carbon dioxide rather than either methylene chloride or ethyl acetate. High pressure is utilized in this method of making decaf coffee. When the beans have been soaked to allow the caffeine molecules to become solvent, they are placed in a high-pressure chamber. The solution essentially becomes soda water. The carbon dioxide doesn't affect the other molecules in the bean, only the caffeine, so the stimulant is safely and effectively extracted.
So there we have it. Science has figured out how to remove the world's favorite stimulant so that those who suffer high blood pressure, or those who have a caffeine allergy, are not adversely impacted. Thus, everyone can enjoy one of the world's most common and popular beverages. Cheers!
