It is a fairly accurate statement that, although decaffeinated coffee has
been produced since the early years of the 20th century, most of it was
rather tasteless, at best, before about 1980. During the mid-80s, most
likely due to numerous unfounded health scares about caffeine, there was
an unprecedented interest in decaffeinated coffee. Almost immediately the
flavor of decaffeinated coffee improved immensely, and all the major
brands of supermarket coffee offered such a version. The decaffeination
processes were changed very little, if at all.
The Swiss Water Process, patented by Coffex
SA in 1979, needed several years to acquire a wide following, and many
coffee companies are still producing decaffeinated beans that are not
water-processed. So why did decaffeinated coffee start tasting good? The
answer is that suddenly there was a market for it. For years only the very
committed health enthusiast had drunk decaffeinated coffee, and coffee
companies did not bother to use good beans for such a low-profile product.
By about 1987, when decaffeinated sales
represented around 25 per cent of the massive United States coffee market,
coffee companies, in order to cash in on the phenomenal demand, started
using higher quality beans for decaf products, and the flavor improved as
quickly as the market grew.
Since caffeine is almost tasteless, except for a slight bitterness, its
removal should not interfere with the coffee flavor at all, unless the
decaffeination process inadvertently extracts flavor compounds as well as
the caffeine. The goal of all decaf processors has been to remove only the
caffeine, not the flavor. It is the quality of the beans that will
ultimately determine the flavor of the coffee.
For around 200 years it has been known that, while caffeine survives
roasting, retaining its properties through temperatures as high as
240°C/475°F, it is completely vulnerable to liquid, and will pass from
green (unroasted) coffee beans into any liquid in which they are soaked.
Some liquids extract the caffeine faster than others.