The two main traditional systems are: wet processing
using water, and dry processing using no water. These are
clearly described in topic box 11.01.01 whereas topic box 11.01.02
provides a schematic overview of both processes. Wet processed
coffee is usually called 'washed' whereas dry processed coffee is
mostly known as 'natural'. Coffee quality generally is discussed in
some considerable detail in chapter 11 - Coffee quality.
Over time the traditional wet process has evolved into a much
more efficient system, using relatively little water and taking
great care with the treatment of waste. Websites where one can view
some of today's modern equipment include www.pinhalense,com.br and
www.penagosclausen.com
.
The dry process has evolved an interesting variation, developed
in Brazil. Here the cherries are pulped as in the wet process but
then they are dried immediately, without any further processing so
with the mucilage adhering to the parchment. The obvious advantage
is that the tonnage to be dried is reduced considerably but a
further plus is that the quality, the taste of this coffee is
better and more stable than what is delivered by the original
'natural' process. These coffees are known today as 'pulped
naturals' and we expect their importance to grow over time, thus
creating a third important processing system. For more on this see
also QA 008 in the Q&A Archive on this site. Other interesting
sites from which to gather information on coffee generally include
www.ico.org, www.supremo.be and www.sustainable-coffee.net.
More scientific information can be found at www.café-asic.org.
Posted 22 October 2005