La Palma Y El Tucan should really be credited for bringing the Lactic process into the limelight. It is essentially anaerobic fermentation but the concept behind it is to enhance the lactic acid activity as a result of carbohydrate fermentation. The control measures they take with PH and temperature ensure that lactic bacteria is promoted and other microorganisms are controlled. An acidic environment (between ph 5 and 7) and a warm environment (18-25 degrees celsius) makes it uninhabitable for many yeast and bacteria strains. This type of fermentation contributes to the organoleptic profile of the coffee. 

Whole cherries are placed in a closed tank. Sugar content, temperature and pH are noted. The high sugar content of the perfectly ripe cherries provides ample food for yeast and bacteria naturally present in the air and on the cherries, so fermentation begins. One by-product of this fermentation is carbon dioxide. As the tank is closed it will slowly fill up with CO2 and the air will be chased out creating the anaerobic conditions. 

Mossto is a new adjunct in coffee processing. The name is loosely borrowed from the winemaking term “must”, meaning the resulting liquid from crushing fresh grapes (including the skin, seeds and stems). In coffee it means just the juice (sans skins etc) and since our focus is the seed and not the juice, used differently. Our industry is still feeling out how best to use it but we do know that by putting the juice from depulping into the fermentation tank we have the opportunity to jump start the fermentation through the introduction of additional micro biomes, plus of course additional sugars. All of this enhances the fruit character and aromas. 

El Diviso was picked and allowed to rest in open tanks for 12 hours at 25 degrees C. Then it was put in bags and left to rest for another 50 hours at 16 to 18 degrees C. Next the whole coffee cherry was fermented in a medium made up of 20% mossto which was set quite warm at 45 degrees C and stirred every 3 hours for another 18 hours. A few sleepless nights were put into this one! 

Anaerobic fermentation is a pretty popular way of processing coffee these days. It is quite easy to do and is not really a new concept but rather an enhancement of old concepts. So by this measure, it is accessible to lots of producers without having to spend heaps of money on infrastructure. By simply putting a lid with an airlock on the fermentation tank you create a whole new spectrum of flavours. 

We really like this example because it takes all the good things already present in a Colombian Gesha and simply turns up the dial on them. Our friends at El Vergel do a magnificent job at carefully controlling this method (primarily controlling time and temperature), as it can go rather pear shaped if not done correctly.