Coffee has taken an important place in human society for at
least 1200 years. Its consumption, which probably originated
in northeast Africa, spread out to the Middle East in the 15th
century and thence to Europe. After oil, coffee has become the
second most valuable commodity around the world. Today,
coffee is among the most widely consumed pharmacologically
active beverages, and its consumption has become a regular
part of daily life worldwide. It is estimated that more than half
of Americans drink coffee every day. The average consumption
for a person in the European Community is 5.1 kg/year, which
is similar to that in the United States.1
In fact, coffee is a complex mixture of chemicals, and is the
main source of caffeine in many populations. However, it also
contains thousands of different chemicals, including carbohydrates,
lipids, nitrogenous compounds, vitamins, minerals,
alkaloids, and phenolic compounds (Fig. 1