Carbonic Maceration

Carbonic maceration was introduced to specialty coffee by Sasa Sestic — the 2015 World Barista Champion — who used it in his winning coffee. He drew direct inspiration from France's Beaujolais region, where the technique is used to produce uniquely fresh wines.

The key difference from regular anaerobic fermentation: in carbonic, whole cherries enter a sealed tank filled with CO2. The CO2 penetrates the fruit's cells and triggers intracellular fermentation — enzymes inside the fruit itself begin working, not just external bacteria. This produces a completely different aromatic profile, with bubble-gum notes, ripe tropical fruit, and sometimes a character that doesn't resemble regular coffee at all.

Process: ripe cherries are hand-selected, enter the sealed tank whole, CO2 is introduced to displace oxygen, fermentation lasts 2-8 days depending on strategy. Only afterward are the cherries depulped and the beans dried.

Advantage: a wild aromatic profile, unlike any other method. Downside: very expensive method (CO2 requires professional tanks, temperature control, daily monitoring), and considered to 'mask' some of the variety's genetic character. Buyers split — some love it dramatically, others prefer the classics.