Coffee beans processing

Four methods of industrial processing of green coffee beans are used:
*Roasting, an essential process to develop coffee’s aromatic properties. Roasting changes the appearance, consistency, smell, flavor and composition of the coffee. Roasting coffee beans causes the bean to expand and become more dense, and brings out the natural oils found inside.

*Grinding
When broken down by grinding, coffee cells release their content of pyrolytic gas formed at roasting. This gas is mostly composed of CO2 and CO, accompanied by small amounts of hundreds of volatile chemical species.

The volatiles only present in low concentrations but are essential bringing forth the typical coffee aroma.

*Percolation followed by dehydration to obtain soluble coffee. In percolation process, more coffee beans are used, with a shorter percolation time. This give a strong flavor but avoids the bitterness.

Percolation refers to the coffee making process in which crushed coffee beans are broken up, mixed together, brought into collision and recomposed in a percolator to extract the full flavor of the coffee.

*Decaffeination
Caffeine is removed by soaking the beans on water or by using solvents or carbon dioxide. The last is thought to be the best method as it does not affect the flavor and there is no residue.

Prior to processing, green coffee beans are cleaned and dusted by pneumatic separating machines, then stored in partitioned soils.

Harvested coffee beans begin to ferment almost immediately and if the crop is not to be lost, it must be processed within 8 to 36 hours after picking.

Processing must remove the seeds of the coffee berry – the source of coffee as a beverage – from the surrounding organic material.
Coffee beans processing