Methylene chloride decaffeination: bad process: or bad press?
O.K., O.K., I'm guilty of turning up my nose at methylene chloride decaffeinated coffee. When buying green beans for our family's gourmet roast house, I didn't even look at a sample of decaffeinated coffee other than Swiss Water Process; somehow, chemically decaffeinated coffee seemed "bad", and coffee decaffeinated with pure water was "good."
My decision to like water decaffeinated coffee and dislike chemically decaffeinated coffee had nothing to do with logic, it didn't even have to do with taste, (generally, I do not drink decaffeinated coffee). It had to do with the bad press it was getting.
I had read somewhere that drinking chemically decaffeinated coffee caused cancer, and the chemical used to decaffeinate the coffee was also banned for use in hair spray. After that, you couldn't give me chemically decaffeinated coffee.
Years later, I still have mixed emotions. Friends in the coffee business tell me methylene chloride decaffeinated coffee has the best taste, is the least expensive decaffeinated coffee on the market, and poses no health risks. It sounds great, but I've still had a hard time getting past the idea of the chemical.
My curiosity aroused, I decided to do a little digging and pulled out the books, opened the file folders, made a pot of caffeinated coffee, and got on the telephone to my coffee friends to see what I would find out about methylene chloride decaffeinated coffee.
What is methylene chloride?
Methylene chloride is a colorless liquid with a slightly sweet aroma and has a boiling point of 104 [degrees] F.
How is it used to decaffeinate green
The beans are treated with steam in order to draw the caffeine from the inner bean to the outer surface area. Once this has been done, the solvent (methylene chloride) is applied directly to the beans, removing the caffeine. Steam is again applied to the coffee, driving out residual solvent. Then the beans are dried and roasted just like any other green coffee.
Why is this method supposd to be
Methylene chloride is a selective solvent, removing only the caffeine and wax from the beans, leaving the coffee's flavor largely intact.
Does any of the chemical remain in
the bean after the decaffeination
process is complete?
Minute traces. Methylene chloride evaporates at 100 to 200 [degrees] F; beans are usually roasted at temperature of 350 to 425 [degrees] F, and coffee is brewed at 190 to 212 [degrees] F. Any amounts of methylene chloride left in brewed coffee would be less than one part per million.
Does methylene chloride cause
cancer in laboratory animals?
According to a report published on August 9, 1985, in the Journal of the American Medical Association, studies of rats fed regular and decaffeinated coffee (at doses equivalent to 70 or 80 cups of coffee per day) or fed methylene chloride in their drinking water (at doses equivalent to 125,000 to 6,250,000 cups of decaffeinated coffee per day) showed no evidence of carcinogenicity. . . . Hence, scientific evidence suggests that methylene chloride is safe for use as a solvent in decaffeinating coffee.
Is methylene chloride also used in
paint removers and hair sprays?
According to Dr. Samuel Lee's column published in this magazine in March, 1987, methylene chloride belongs to an important family of chemical compounds with widespread uses, (this family is) called halogenated hydrocarbons. It is prepared by the chlorination of methane, the major component of natural gas. Methane is a compound of a single carbon atom with four hydrogens, each replaceable by chlorine.
How you replace the hydrogens with chlorine determines what your end result will be. When all four of the hydrogens are displaced, you get a heavy liquid that can be used as a dry cleaning solvent, spot remover, and as a fire extinguisher.
When three of the hydrogens are replaced by chlorine, the result is chloroform, used for over a century as the anesthetic in surgical operations.
When only two hydrogens are replaced by chlorine, the result is methylene chloride, and when only one chlorine is included we get methyl chloride (widely used by physicians and dentists as a local anesthetic).
If the process is non-toxic, inexpensive and the decaffeinated
coffee tastes good, why are consumers so
wary of it?
The dreaded "C" word, exaggerated reports of suspected carcinogenicity.
I spoke with several roasters about methylene chloride decaffeinated coffee. Every one of them agreed that the process was safe, inexpensive, and produced a great tasting cup of decaffeinated coffee. They also said that in their opinion, it was just a question of time before the Food and Drug Administration outlawed the use of it entirely. It would be outlawed not because it was actually harmful, but because of the public's perception that it was harmful.
You have to make up your own mind how you feel about this process. If you are the type that doesn't take aspirin, eat while sugar, has low cholesterol, and exercises every day, you probably won't want to take the one in a million chance that you may develop cancer as a result of drinking coffee decaffeinated with methylene chloride. However, if you are like me and just want to be able to drink an occasional cup of decaffeinated coffee that has some taste, keep an open mind about it and give the coffee a try.
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|Publication:||Tea & Coffee Trade Journal|
|Date:||Feb 1, 1991|
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