It has been a few years for CM(carbonic maceration) processed coffees revealed in the specialty coffee scene. And its impact in the industry has been great as the processing method has very unique characteristics and positive impacts on coffee flavour and quality.
Basically, the CM process is not as the traditional washed or natural processed. Maybe it is not right to call it 'process' as the CM process is, technically, a 'pre-process', not 'process' that we normally mention.
The carbonic maceration process is from the wine's processing technic, JULES CHAUVET from Beaujolaus. The CM technic is done before the coffee cherries go to the main processing such as washed or natural or honey.
After picking the cherries, the producer puts coffee cherries inside a stainless-still container, and to remove oxygen, charge carbon dioxide from the bottom of the tank as carbon dioxide is denser than oxygen, therefore, an anaerobic environment is created.
After the fermentation, then, coffee cherries are processed as washed or natural or any other method preferred.
The benefit of CM process is that bright fruity notes and unique flavours are elevated such as strawberry, raspberry, cherry, and tropical fruits. Therefore, the flavour of coffee becomes very unique and special.