Now, where were we? Ah, yes. Roselius, in a rage-filled bid for vengeance, murdered caffeine in coffee and successfully avenged his deceased father. Confused? You should check out last week's post real quick. For everyone else, we were just getting to the awesome part!
The Awesome Part
There are a number of ways of decaffeinating coffee now and, in general, there are two categories: solvent-based and non-solvent, or "natural," decaffeination. We'll get back to those suspicious quotation marks later.
Within the solvent-based category, there are two kinds of decaffeination. Here's how it goes:
1. Coffee beans are blanched which extracts most of the caffeine, oils, and other chemicals that give coffee its fantastic flavor.
2. Beans removed, the water solution is subjected to a wash of methylene chloride and/or ethyl acetate for nigh on half a day. The molecules of the solvents bond with the molecules of the caffeine.
3. The solution is heated and all the garbage evaporates away. Sadly, they take caffeine with it - their unwilling hostage.
4. Beans are placed in the water to reabsorb their oils and flavors.
This method is dead popular in Europe, and so we call it the Euro Prep.
1. Coffee beans are steamed to widen their pores. Creepy.
2. The beans themselves are subjected to the same solvent wash as in the Indirect Method.
3. The solvent wash, with the bonded caffeine, is drained away.
4. The coffee beans are steamed again to remove residual chemicals.
Now, though this process uses chemicals, things like ethyl acetate are naturally occurring in plants, so this method is often called the "Natural Decaffeination Method." We'll let you think of that what you will.
There are two other methods, ones that we consider perhaps more "natural" and certainly more appealing.
In this category, we also find two methods.
We referred to this first one last week as the Supercritical Carbon Dioxide Method. This is the most recent method discovered at the Max Planck Institute
1. Coffee beans are soaked in water and placed in an air-tight contained.
2. Liquid CO2, which selectively separates only the caffeine from the beans, is forced into the container at high pressures.
3. The CO2 is then transferred to another tank, the pressure released, and the liquid returned to gaseous state. The caffeine just falls away.
Finally, the process that created the decaf coffee we offer at the shop:
Swiss Water Process:
As you can guess, this was figured out by the handy folks in Switzerland. Today, this is the approach used by the Swiss Water Company, who probably have a patent on the process, but don't quote us on that - I just made it up. Here's how it works:
1. No Chemicals.
2. Beans soak in what amounts to a hot tub for awhile. Then, the water is drawn off. Most of the oils, caffeine and other chemicals in the beans are int he water.
3. This water soak is passed through a charcoal filter. Because caffeine molecules are larger than others in coffee, the water is effectively "decaffeinated" at this point, while maintaining all the other good stuff.
4. This water, caffeine free but flavor and oil rich, is then used to soak another batch of coffee beans. This time, caffeine is drawn out, because there is no caffeine in the water, but there's no room for the flavor and oil compounds, so they stay put in the beans.
5. The caffeine-filled water is then filtered again and reused on the next batch of beans. Pretty ingenious, we think.
If this doesn't sound as effective as chemical decaffeination, then you should know that the USDA only requires "decaf" coffee to be 97% decaffeinated. The Swiss Water Process coffee beans, however, are regularly tested to ensure that they are just around 99.9% decaffeinated. Not too shabby! Here is a cool graphic to help explain a bit more:
Credit: Righteous Bean
Labeling a decaffeination process as "natural" can get tricky. While the solvent-based methods are often called natural, so are the non-solvent based ones. It sort of depends on your definition of "natural." And "chemical." And "coffee."
There are some coffee purists, of course, who believe that because coffee is itself naturally caffeinated, then any attempt to decaffeinate it is inherently unnatural. They my have a point.
But, when I'm enjoying a 500-calorie brownie at 11 PM because I just can't get through the next episode of Grey's Anatomy without a little chocolate courage, I don't want to wash it down with a giant cup of I-guess-I'll-just-be-up-all-night.
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