Hugo Luiz Portes da Silva works for Carmo Coffees in Brazil. They are based in Minas Gerais near Saul Paolo. Carmo oversees the processing and management of 17 farms, producing outstanding quality in southern Brazil. They operate a New Flavours Program which was developed to find new ways to improve the quality of Brazilian arabica through breeding and processing technologies. A major area of focus for Carmo is semi-carbonic maceration (Semi-CM). We talk to Hugo about how they have turned equipment originally developed for the dairy industry into state of the art fermentation tanks. The interview includes written and audio files.
BH – We understand you have been pioneering a new processing method that is a kind of hybrid between anaerobic and natural. Can you explain it to us?
HP – Natural Process apparently seems to be the simplest process when compared to others which involves more steps. One of the biggest challenges with the Natural Process is delivering fruity flavors in a clean cup, without the off flavors (probably caused by overripe cherries — “passa” in Portuguese) or astringency (probably caused by underripe cherries — “verde” in Portuguese). So, sorting the cherries with different maturation stages on the ‘lavador’ equipment is critical, as the cherries are in most cases harvested mechanically at once (or semi-mechanically — ‘derriçadeira’).
With the learning curve achieved in the natural process, the natural step, I might say, would be to take the process to the next level: selectively picking the cherries at their maturation peak (Brix) and later subjecting them to a controlled fermentation process (wet or dry) in airlocked stainless-steel tanks — the Natural Anaerobic Fermentation Process was born.
BH – How long does the process take?
HP – Time will fluctuate with other process indicators variation (Brix, pH, Temperature, and Oxygen). In general, the fermentation time can vary from 12 to 96 hours. The duration of the process is not fixed, and the fermentation can be ended once the target pH is reached.