The coffee decaffeinated is green coffee which caffein has been eliminated him most of.This reduction of cafeínico content is obtained by means of an industrial process of extraction that maintains the conditions organolépticas of the raw material, within a specified rank.
Caffein is defined as the component physiologically more assets of the coffee and confers tonificantes properties for the human organism:
*Reduce the fatigue
*Aumenta the attention capacity *Disminuye irritability
*Mejora the state of humor and the general well-being
With the intention to diminish the loss of aromas and flavors, in most of descafeinización processes, the extraction of caffein takes place in the grain of green coffee, before being toasted and being ground.Nowadays, the processes have improved sensibly, until the point to reach extraction performances that oscillate between 97-98% of total caffein.
By chemical dissolvents:
The descafeinización by extraction of the caffein of prehumectados grains of green coffee with an organic dissolvent is, until today, the extended process more.The most effective dissolvents are the Metileno chloride (DCM) and the ethyl Acetate (AE).
The process of descafeinización by dissolvents is made generally of way discontinues working in batch of greater or smaller size. In order to decaffeinate 1 ton of coffee approximately 10 kg of dissolvent are used.Caffein is extracted of grains of green coffee previously humectados, by means of successive extractions, until reaching the practical elimination of caffein.Later, the grains are dealt with water steam to eliminate the dissolvent until inferior contents the established legal limit.The process finishes with the drying of the coffee by means of hot air until reaching the initial humidity approximately.
The descafeinización by water supposes 22% of the world-wide capacity.
The process by water is made according to the following stages:
Successive extractions of grains of coffee previously humectados with extract of free green caffein coffee, until reaching the legal caffein limit.
Separation of the caffein of the obtained liquid extract previously by means of absorbent (an activated charcoal, ion exchange resins...)
Recovery of the extract for its later use.
Recovery of the caffein of the absorbent one used by different techniques:washing with water and alcohol, water to high temperatures...
The main advances in this process of descafeinización have been carried out fundamentally in the field of the absorbent ones used to separate the caffein of the liquid extract.
Descafeinización by supercritical fluids CO2:
It is the application of supercritical fluids for the caffein extraction of grains of green coffee. The CO2 is the used dissolvent more although others exist.
At the moment, this method represents the 20% of the world-wide production.