Altos Anaerobic

Altos del Abejonal sits at 1800 metres above sea level in the Tarrazu region, only 70 kilometres south of the Costa Rican capital San Jose. The Talamanca Sierra runs through the region, with peaks of above 3000 masl. The farm is also close to the regional capital of San Marcos, which sits at 1350 masl and is home to 9000 people, providing the hub to an area famous for its high quality coffee production. The volcanic soil and afternoon cloud cover in the region provides the perfect conditions for Mauricio to produce excellent coffees at Altos. This lot was created using a rather new process, part of an experiment we started with Mauricio last year. This year we have been able to purchase a much larger lot, and are excited to be able to share it with many more people than last year. Inspired by processes we have seen from some of our progressive producer partners, we attempted an anaerobic pre-fermentation. The coffee is first pulped mechanically, removing most of the fruit, as with the white honey process. The parchment coffee and almost gel-like mucilage are then packed tightly into a small fermentation tank, and sealed with almost no oxygen present. As the fermentation starts to occur, carbon dioxide is produced, creating an almost completely anaerobic environment, and raising the pressure within the tank. This affects coffee flavour in two ways. An anaerobic environment favours a very different set of fermenting bacteria and yeast, leading to a dominant lacto-fermentation. The pressure also forces coffee juices into the seed itself, adding more fermentable sugars to continue the process. The coffee is then dried with the mucilage still attached, as with a honey processed coffee. All of this adds layers of complexity to the final cup, and a very clean and juicy character, a very distinctive and wild expression of the Altos terroir.