For a while, we didn’t offer decaf coffee at City Boy. We were waiting for the right moment to come along and during that time we tried a lot of different decafs. You may not have considered it, but something has to be done to remove caffeine from your coffee and there are various methods one can use to do it. Here are a few:
Ethyl Acetate (EA) Decaffeination
Ethyl acetate (EA) decaffeination uses a special liquid called ethyl acetate to remove caffeine from coffee beans. Think of ethyl acetate like a sponge that only soaks up caffeine. While “ethyl acetate” might sound scary, it’s actually found in things like fruit and sugarcane, so it’s considered a fairly natural way to decaffeinate coffee. The process starts by steaming the beans to open up tiny pores on their surface. This allows the EA to get inside the bean more easily. Then, the beans are soaked in a mix of water and EA, where the EA acts like a magnet, pulling the caffeine molecules out of the beans. This soaking process happens a few times to make sure most of the caffeine is gone. After that, the beans are steamed again to get rid of any leftover EA. Finally, the beans are dried back to 11% moisture content, which is appropriate for roasting.
Carbonic Natural (Supercritical CO2) Decaffeination
Carbonic Natural (Supercritical CO2) decaffeination uses carbon dioxide (CO2), the same gas we breathe out, to remove caffeine. You might be thinking, “Wait, how can air remove caffeine?” Well, in this method, the CO2 is cooled down and put under pressure to turn it into a liquid. This liquid CO2 has a special ability to dissolve and trap caffeine. First, the coffee beans are soaked to help the liquid CO2 get inside. Then, the beans are put in a special container with the liquid CO2 where the CO2 molecules swirling around the beans and grab onto the caffeine molecules. Once the liquid CO2 has absorbed the caffeine from the beans, it’s moved to a separate chamber where the pressure is reduced. This causes the CO2 to change back into a gas. The caffeine is released and stored to be sold.
Swiss Water Process
The Swiss Water Process is a chemical-free way to remove caffeine. Like previous processes, it starts by soaking the coffee in water to open up the pores. Then, the beans are placed in Green Coffee Extract (GCE). GCE is made by soaking coffee beans in water, then filtering out the caffeine. When the regular coffee beans are put in the GCE, the caffeine from the beans starts to move into the GCE. This happens because of a natural process called diffusion. Imagine putting a drop of food coloring in a glass of water – the color spreads out until the whole glass has the same color. Once the caffeine has moved into the GCE, the GCE is filtered to remove the caffeine. The process is repeated for 8-10 hours until the level of caffeine left in the beans is negligible.
Enjoying Decaf Without Compromise
So, there you have it – a glimpse into the world of decaffeination! If you’d like to learn more, you’ll be able to watch our friend James Hoffman tour the facilities that do these processes via his Youtube channel.