Welcome Decaf Coffee Lovers!

Coffee naturally contains the active supplement
caffeine. The stimulating power of coffee is as well
known as the outstanding taste. A lot of people
appreciate this stimulating power, but there are
some people that do not handle caffeine so well or
do not like the stimulating effect every time of the
day. For them there is decaffeinated coffee on the
market. This decaffeinated coffee lacks the stimulating
power of caffeine.

Normal coffee beans contain between 0.8 percent
and 2.5 percent caffeine depending on origin and
variety. Decaffeinated coffee is not entirely caffeine-free.
In European Community (EC) countries, roasted
decaffeinated coffee may contain a caffeine residue
of 0.1 percent and coffee extract 0.3 percent.

Decaffeination processes

To make coffee caffeine free, the stimulating
supplement needs to be derived from the beans.
Since coffee develops most of its flavour during
roasting, the caffeine is extracted from the raw green
coffee beans. Various methods exist to achieve this,
of which the water-carbon (H2O/C) and dichloromethane
(commonly known as DCM) methods are the most
used. Both of these techniques extract the caffeine
with a caffeine-selective solvent, which therefore
leaves the other substances in the bean. Modern
decaffeinating methods have no effect upon the
flavour and aroma of the coffee. Good decaffeinated
coffee therefore tastes almost the same as coffee
containing caffeine.

Water-carbon method

This process uses water (H2O) as a solvent.
The green beans are rinsed with water for a
long period, during which time the caffeine
dissolves into the water. The water, with its
dissolved caffeine, is then pumped through
an active carbon (C) filter which absorbs the
caffeine. The decaffeinated beans are dried
using warm air and then cooled with cold air.
They are then roasted, ground and packed in t
he usual way. The water is re-used for the
decaffeination process.

Dichloromethane process

This method employs dichloromethane (DCM)
as a solvent and has been developed to suit
the requirements of the out of home industry.
The green beans are moistened with water in
order to make the surface of the bean porous,
and soaked in the solvent for 30 minutes. This
is repeated several times. The beans are removed
from the solvent once the caffeine has dissolved.
They are then steamed for some time in order to
remove any remaining solvent. Afterwards the
beans are dried using warm air, then cooled with
cold air. They are roasted, ground and packed in
the usual way. The dichloromethane is reused
for further decaffeinating.

source: Douwe Egberts