So, just to clarify, the carbonic maceration is not to be considered as a new method to process the coffee but rather, a step that can be included in the washed or natural method. In the washed carbonic maceration the ripe coffee cherries are handpicked, sorted and depulped before introduced in a sealed tank.
What is macerated coffee?
Does carbonic maceration use yeast?
Unlike standard fermentation, in which yeast is manually or naturally added to grape must to convert sugar into alcohol, carbonic maceration does not use yeast to start fermentation. How is this possible?
What is the carbonic method for coffee fermentation?
In the carbonic method for coffee fermentation, first, the coffee cherries are siphoned to remove low-density “floaters,” then added to an airtight tank with a one-way valve, much in the same way as in the anaerobic method. Because the skins of the cherries are left in tact, fermentation may take days or weeks.