Clicking on banner ads keeps JWR alive
Jewish World Review Feb. 19, 2002 / 7 Adar, 5762

Dr. Ed Blonz

Blonz
JWR's Pundits
World Editorial
Cartoon Showcase

Mallard Fillmore

Michael Barone
Mona Charen
Linda Chavez
Ann Coulter
Greg Crosby
Larry Elder
Don Feder
Suzanne Fields
Paul Greenberg
Bob Greene
Betsy Hart
Nat Hentoff
David Horowitz
Marianne Jennings
Michael Kelly
Mort Kondracke
Ch. Krauthammer
Lawrence Kudlow
Dr. Laura
John Leo
David Limbaugh
Michelle Malkin
Jackie Mason
Chris Matthews
Michael Medved
MUGGER
Kathleen Parker
Wes Pruden
Sam Schulman
Roger Simon
Tony Snow
Thomas Sowell
Cal Thomas
Jonathan S. Tobin
Ben Wattenberg
George Will
Bruce Williams
Walter Williams
Mort Zuckerman

Consumer Reports


Is decaf dangerous?


http://www.NewsAndOpinion.com -- DEAR DR. BLONZ: My husband and I have been drinking decaffeinated coffee and tea for years, partly because of health reasons. A close friend has told me that it is more dangerous to drink decaf because of the way it is processed. Will you please enlighten me on this subject? - S.A., San Diego, Calif.

Dear S.A.: A population study in the journal Arthritis and Rheumatism (January 2002) reported a increased risk of rheumatoid arthritis in women drinking more than four cups of decaffeinated coffee per day. It was a finding of the Iowa Women's Health Study, but no other research has made this connection. No relationship found between drinking caffeinated coffee and getting arthritis, and those drinking tea were found to have a decreased risk. With this type of study it is unclear what, if anything, is causing what.

Thus, it's inappropriate to conclude that decaffeinated coffee might increase the risk of developing rheumatoid arthritis. Aside from this study, there do not appear to be any additional health risks associated with drinking decaffeinated coffee.

We should discuss the ways in which coffee and tea are decaffeinated. One thing they share is a need for a solvent that does a good job of dissolving caffeine. This solvent can be water, methylene chloride, ethyl acetate, triglycerides, or pressurized carbon dioxide. An indirect method involves taking a load of green coffee beans and placing them in a quantity of water. All water-soluble substances -- including caffeine -- is then drawn into this water. At this point, the solution includes components that give coffee its desirable aroma and flavor. This solution is removed from that first batch of coffee beans, and those beans are discarded.

The next step is to remove only the caffeine from the solution, which is accomplished by using a selective caffeine solvent that effectively pulls the caffeine out of the water. The caffeine-rich solvent is then separated from the water extract.

At this point, the water extract contains the water-soluble portions of the coffee bean -- minus caffeine. This now becomes the working solution into which the next batch of (caffeine-containing) green beans are placed. Only the caffeine gets extracted in this second mixture, as all other components are already there and will exist in a state of equilibrium between what is in the beans and what is already in the solution. This second solution then goes through its caffeine extraction, and the process continues with subsequent batches.

Another indirect process is called the Swiss water process. It is similar to the above, except that the caffeine is not removed from the water mixture by solvents. The Swiss water process passes the caffeine-rich water mixture through charcoal filters pre-treated with substances that grab the caffeine. The caffeine-free water mixture is then mixed with the next batch of green coffee beans, and the process continues.

The direct method involves mixing the selective caffeine solvent directly with the beans (or tea leaves). Methylene chloride and ethyl acetate are the solvents most often used.

After it has had a chance to dissolve the caffeine, the solvent is removed, and the beans/tea leaves are steamed gently to eliminate any remaining solvent residue.

Methylene chloride is a carcinogen, but there shouldn't be any left to pose a health risk. This is because methylene chloride evaporates at around 110 F -- well bellow steaming temperature and well below the temperature at which coffee and tea is brewed.

Ethyl acetate is a compound that occurs naturally in fruits and vegetables and is the one most often used with tea leaves. In all the above, the green beans or tea leaves are ready for drying, roasting or further processing after the caffeine is removed.

There is a newer, more expensive method that utilizes carbon dioxide that has been liquefied under high pressure. (This is the only process approved for organic coffee and tea production.) The liquefied carbon dioxide dissolves the caffeine from the tea leaves or coffee beans and is then drained off. Yet another method utilizes the fatty substances called triglycerides. Whatever the method, decaffeination technology has improved greatly over the years, and flavor differences may be hard to detect. Much also depends on the quality of the beans and tea leaves, together with the particular practices of the roaster.

Note that the use of the term "water process" with decaffeinated beans doesn't tell you the whole story, as most indirect methods utilize a water extraction somewhere along the way. If the label states "Swiss water process" or has other additional information, a better determination can be made.



JWR contributor Ed Blonz, Ph.D., is a nutrition scientist and author of Power Nutrition and the "Your Personal Nutritionist" book series. Send questions to him by clicking here.

Up

02/12/02: Do veggies prevent mineral absorption?
02/05/02: Incompatibility problems between calcium and vitamin C; Can supplements prevent blindness?
01/29/02: What's wrong with the meat?; Does tuna packed in water still have high levels of omega-3?; Avoid "fractionated vegetable oils?"
01/22/02: Is all soy milk created equal?; foods containing magnesium; why do vitamins expire?
01/15/02: Three cheers for chocolate?
01/08/02: Making sense of labels
01/03/02: "Thermogenic" weight loss
12/26/01: What's up with ephedra?
12/18/01: Is new supplement a scam?

© 2002, NEA