Over the last century, several techniques — many of them exceedingly toxic — have been used to separate your coffee from its caffeine. In early efforts, toxic solvents such as benzene and chloroform were used (and we wondered why that early low-octane brew tasted so weird). In the early 1970s, dichloromethane became the solvent of choice because of its lower toxicity and ability to dissolve caffeine without eliminating the ingredients that give coffee its flavor. However, evidence soon surfaced that this chemical might be carcinogenic, and its use was drastically curtailed.
Ethyl acetate then became the replacement for dichloromethane, and was touted as “natural” because the chemical is present in fruit. Unfortunately, studies found that it, too, is moderately toxic.
In recent years, two non-toxic and environmentally more benign methods have been used: water processing and supercritical fluid carbon dioxide. In the water processing, hot water extracts both flavor ingredients and caffeine from green coffee beans. This extract is passed through activated charcoal which removes most of the caffeine. The original beans are then soaked in the decaffeinated extract, which restores most of their flavor.
A refinement of this technique is the Swiss water process, in which super flavor-charged water extracts the caffeine from green coffee beans, which retains flavor without the use of harsh chemicals.
Plans are now in the works to genetically engineer coffee and tea plants so they are incapable of producing any caffeine. Whether or not that’s a desirable alternative is anybody’s guess. Until then, make sure your decaf is water-processed, or just reach for the herbal tea.
K.C. Compton is the editor-in-chief at The Herb Companion.
Click here for the original article, Health Alert: How Much Caffeine Is Too Much.