Coffee beans all contain caffeine. From the beginning they have and always will. That is what the Ethiopian goat herder Kaldi noticed about his goats eating the coffee “cherry” fruit from the coffee tree. They were basically under the effects of caffeine and would not sleep. That had to be funny! As a result and after a few other tests, coffee was born. That was way back when over 1000 years ago. Even though all Arabica coffee beans contain caffeine, to some it’s more of a nuisance than a stimulant so some prefer it gone. How do we get this unofficial legal ‘drug’ of sorts out? That, my friend has many answers.
The first process we will discuss is a chemical process using methylene chloride. It is also called the European Process (EP or KVW). In this method of decaffeination, the raw green coffee beans are soaked in near boiling water. This extracts the flavor oils and the caffeine from the coffee. The water is then separated and put into a tank where it is treated with the chemical methylene chloride. This chemical sticks to the caffeine and is then removed from the flavor oils. The beans are brought back into the mix and they absorb the once lost flavor oils. It has been my experience and arguably some other coffee geek’s as well that these decafs processed with methelyene chloride taste the best. The quality of the cup is superb over other decaf processes, as long as the beans are processed and hulled correctly at origin.
Methelyene chloride sounds bad but it really is a safe method to decaffeinate coffee beans because is it never absorbed by the bean. It is really a solvent and will not bond with the coffee; just with the caffeine. However this chemical method can cause some sensitive tummies to become agitated because there are traces left behind. I have found that most people that have this irritation usually know what is from and ask me if my decaf is processed with it.
Another decaffeination method is called ethyl acetate. This process is called the ‘natural process’ because ethyl acetate is a chemical compound found in some fruits. This process happens the same way as the methelyene chloride process above; the difference is that ethyl acetate is a natural chemical vs. methelyene chloride being a man made solvent. I still think a methelyene chloride processed decaf coffee tastes of better quality. However some folks do not notice the irritated stomach as much with this process.
The next decaffeination process we will talk about is the Swiss Water Process (SWP). During this process, the green coffee beans are again soaked in near boiling water. As stated before, this extracts the caffeine and flavor oils from the coffee. The difference in the SWP is that the water is then put into a tank where it is forced through charcoal filters. It is also circulated around in hot water to remove the caffeine. The beans are then brought back into the mix to absorb their flavor again. However, this process allows more flavor oils to be damaged and/or removed affecting the overall cup. Upside is that no chemicals of any kind are used however SWP coffees are higher in price. I do feel that these coffees, though they appear of better quality visually lack flavor and are quite flat.
OK so yet another process to decaffeinate coffee is called the mountain water process or MWP. In Mexico, a company called Sanroke developed this decaffeination process where they use water from the glaciers of the Pico de Orizaba Mountain in Mexico. The process they use is the same as the Swiss Water Process: using water to float the coffee oils and caffeine in a solution, then using a special filter to remove caffeine, and returning the water soluble oils to the coffee. The only difference is that the coffee is awesome! The MWP decafs are very close to non-decaffeinated premium coffees. But they are more expensive.
The last process of decaffeinating coffee is the C02 process. In this process, the raw green coffee beans are mixed with pure water. When the coffee absorbs the water the grains expand and the pores open. This allows the caffeine molecules to become mobile. Then, the carbon dioxide is added to the water making it fizzy, like sparkling water. What happens is the carbon dioxide acts like a magnet and attracts all the caffeine. When the caffeine is captured by the carbon dioxide, it is removed. The carbon dioxide does not touch the flavor molecules so it gives the coffee an excellent taste in the finished decaffeinated coffee.
There is one last ‘unofficial’ decaffeinating process and that is roasting. It’s unofficial because it does not completely decaffeinate, not even 99.9% like the other methods. It’s a lot less. Roasting will burn off caffeine to some extent and the darker the coffee is the less caffeine there is in it. Most of your espresso blends are comprised of dark roasted coffee beans. So you guessed it, when you think you are getting an extra dose of jolt in that extra double shot of espresso think again Jack. Most people think that espresso has more caffeine naturally but not quite!
If you want the extra jolt, try a chocolate bar, a shot of soda, an aspirin or two or a slice of cake made from a box cake mix. Caffeine is a hot commodity! This caffeine is gotten from decaffeinated coffee and added to these products. Yes sold on the resale market. It is big business!
So contrary to some beliefs decaffeinated coffee does not grow on a special tree. It gets that way by man. Like so many other things huh? Many coffees come in decaffeinated versions including organic coffee. When you buy your next bag of whole bean coffee, look to see what decaffeination process is used. You will find that this is not easy with most store bought coffees. You may have to go to your local independent coffee shop or roaster. I bet they have what you are looking for.
My name is Tony DiCorpo, and I am a coffee roaster. I also sell fresh roasted coffee beans, and green coffee beans via my website.