Special Processing: Carbonic Maceration

In our Special Processing Series we are on the lookout for coffee processing techniques which are a bit different from the more traditional methods, resulting in surprising smell and taste experiences. 

Rob says: We are used to call this style of processing Macerated coffee, although officially it’s called Carbonic Maceration. The main thing that differentiates anaerobic coffee fermentation from carbonic maceration of coffee is that in carbonic maceration the cherry is left in tact, and not pulped prior to entering a sealed tank. Carbonic maceration is a term lifted from the wine industry, where whole grapes are fermented without pressing the juice.

Because the skins of the cherries are left in tact, the process is slow and may take weeks. The varying levels of pressure in the tank create different available sugars and pectins for the microbes to macerate. Near the bottom of the tank, the coffees are gently pressed over time by gravity, whereas cherries near the top of the pile remain unpressed and fermentation will occur slowly and almost entirely inside the skin of the fruit.

So don’t expect your average cup of coffee. Be ready for the extra funky twist and enjoy, every sip at a time.