Caffeine-free == sketchy?

April 5, 2006 10:44 AM

How do they decaffeinate soda and coffee?

And does this process make the drinks more suspicious, ala sugar-free substances and their long-term effects.

Thanks!

posted by cgs to health & fitness (19 comments total)

For most soda products, it's easy - They just don't put it in. It's a flavorless additive. Coffee is more interesting, there is some way to soak the beans that breaks down the caffeine molecule. Also, the longer you roast the bean, the less caffeine remains. I am sure wikipedia can give you more detailed background.
posted by mzurer at 10:48 AM on April 5, 2006

how they do it.
posted by jimmythefish at 10:48 AM on April 5, 2006

Yes the beans are soaked in a chemical which dissolves caffeine. They drain off the solvent, wash the beans, and hope that not too much else was leeched out of them. Of course, they don't get it all, and other stuff IS leeched out.

Decaf coffee has about as much caffeine as tea or soda.
posted by scarabic at 10:49 AM on April 5, 2006

Siderail: caffeine is not flavourless, it has a bitter taste that is quite easily identifiable.
posted by lemur at 10:51 AM on April 5, 2006

mzurer: even cola has caffeine added?
posted by cgs at 10:52 AM on April 5, 2006

Ummmm, maybe start with Google?

Second link looks useful.

Water and supercritical CO2 decaffeination would seem to be without any likelyhood of long-term side effects.

Ethyl Acetate is also used. It's a naturally occurring substance, and so its thought that any traces left behind are not going to be any worse for you than the traces in fruit and the like.

The last uses Methylene Chloride, which is, if I remember my MSDS correctly, "known by the state of california to cause cancer." It's pretty volatile, so it seems unlikely to leave a residue, but you never know. I kind of doubt MC is used to decaffeinate coffee anymore, at least not the finer brands. No idea if its still used with Kola nut.
posted by Good Brain at 10:53 AM on April 5, 2006

Oh, man. National Geographic did this great story on caffeine last year, and they had a picture of the stuff that comes out of decaffeinated coffee, and it was just gross.

An excerpt of the story is here, and if you go to the "Sights & Sounds" box on the right, there's a neat little flash presentation on the story by the photographer. In that flash presentation, there's a section called "fluffy stuff", and it describes the decaffeination process and there are some pictures of it.

As for healthy/not-healthy, can't really help you. I always used to find decaf coffee pointless, but then it is really nice after a huge meal if you don't want to stay up all night.
posted by bibbit at 11:06 AM on April 5, 2006

While there are some sources that claim caffeine is bitter, the National Institutes of Health disagrees.

Apparently the kola nut, which is the origin of the distinctive cola flavor, has naturally occuring caffeine, but frankly I don't think there's much in the way of anything natural in mass-produced sodas. I could be wrong, though...
posted by mzurer at 11:18 AM on April 5, 2006

Slightly unrelated, but in regards to your additive comment -- nothing sketchy about aspartame.
posted by trey at 11:21 AM on April 5, 2006

Yeah, my thermodynamics professor is a huge fan of supercritical CO2 decaffeination procedures, because it maintains the quality (of coffee beans, at least). Also, she can start lectures on supercritical fluids with it.
posted by jenovus at 11:21 AM on April 5, 2006

Yeah, the kola nut has nothing to do with modern mass-produced colas, like Coke and Pepsi. If you look on the ingredients lists of those soft drinks, you'll find caffeine listed.

The flavor of modern cola drinks, incidentally, is a mixture of vanilla, cinnamon, and citrus. When it's blended just right it's hard to discern the individual parts, but it's not uncommon in generic brands for one of the component flavors to dominate.
posted by Acetylene at 11:29 AM on April 5, 2006

mzurer: even cola has caffeine added?

They used to remove the cocaine that was naturally present in the coca leaves used to make coca cola.
posted by delmoi at 11:33 AM on April 5, 2006

Alton Brown explained this pretty well. Because decaffination takes out so many of the nutrients and flavor from the coffee bean, you have to use super-expensive super-awesome coffee beans to get decaf that tastes as good as supermarket brand coffee. But since consumers aren't willing to pay more for the decaf version of a particular regular brand, crap beans go in, and crappier beans come out. I don't understand why some people drink the equivalent of O'Douls every morning.
posted by Saucy Intruder at 11:42 AM on April 5, 2006

some sources that claim caffeine is bitter

It's an alkaloid, specifically a xanthine. Alkaloids are perceived by the taste buds as bitter (exceptions are very rare and caffeine is not one of them).
posted by meehawl at 12:02 PM on April 5, 2006

scarabic >>> "Decaf coffee has about as much caffeine as tea or soda."

Tea has more caffeine than regular coffee (depending on varietal).

So decaf coffee actually has rather less caffeine.
posted by dirtynumbangelboy at 12:20 PM on April 5, 2006

Methylene chloride is the active ingredient in old-style, rubber-gloves-and-apron, use-it-outdoors paint stripper.

I'd be a lot more worried about some of the MeCl being left IN the coffe than what extra it might leach out. (If I drank decaf.)
posted by Kirth Gerson at 12:35 PM on April 5, 2006

Sodas, teas, and coffees vary in their caffeine content (or here), but decaf coffee, in general, has far less caffeine than tea or sodas, except for the decaf varieties of each. Most sodas have about 40mg per 12oz serving.

Coffees vary a lot by type and brewing method, but most have quite a bit more than a typical soda. While a decaf coffee has only 6-10mg per 12oz.

Teas vary quite a bit, as well, though most have less caffeine than a cup of joe.
posted by wheat at 1:00 PM on April 5, 2006

While there are some sources that claim caffeine is bitter, the National Institutes of Health disagrees.

They're totally wrong, unless the bitter, obnoxious taste of No-Doz and every other caffeine supplement I've used is due to some additive everybody puts in.
posted by Opposite George at 1:12 PM on April 5, 2006

Reagent grade caffeine (USP 99.9+%) is quite bitter on the tongue; I can attest from personal experience, and most sources agree with me. That NIH link is wrong.

Cola is hardly something that occurs in nature. It's produced in dozens of vats, using naturally and synthetically derived chemicals and flavors. If you examined the equipment used in a cola factory and a pharmaceutical laboratory, you'd have trouble telling them apart.
posted by ikkyu2 at 4:15 PM on April 5, 2006