What is a Natural Process?
The term “natural” can be used to represent such vast and varying concepts that sometimes we don't really know what it means. The term “natural” in coffee processing refers to the drying of coffee berries just as they are picked from the tree. The skin and juices infuse their flavors on the seed as they dry making this process taste so unique. Natural processing is also likely the way all coffee was initially processed. Specific historical data is not available but some accounts mention drying coffee berries on mats in the sun. Theories also suggest that sometime between the 15th and 19th centuries, washed processing for coffee emerged.
The natural process is more common in producing countries that have a lot more direct sun and less rainfall. Regions where using water for processing coffee is just not feasible tend to process their coffee naturally. This saves water, time, and overall resources which all have value (money). Some places where coffee growing is a highly mechanized system (like Brazil) the berries are mechanically dried so that the process is a lot faster and the coffee can be sold quicker providing a faster turnover and cash flow.
In specialty coffee we have noticed that fast mechanical drying of coffee berries renders plain and flavorless coffee - similar to mechanically dried parchment or washed coffee. The slow and controlled process of drying coffee with the skin (as a natural process) renders completely different notes that are exquisite and full of flavor. For tropical countries that have excessive rainfall during the year, it becomes particularly difficult to dry a naturally processed coffee.
Just think of leaving a banana out in the sun during the day for a few weeks. It will most likely grow a fungus. If the berries don't receive sufficient sunlight and heat to ensure a slow but steady drying (dehydrating) process then fungus will grow. The berries also need to be raked regularly to ensure an even drying process.
Our Summer Tanager is one of the naturally processed coffees currently being offered (it is also limited to this season). These berries were left in anaerobic tanks for two weeks after being picked. After this intense fermentation period they sun dried for a whole 30 days. But the process doesn't end there, this coffee has been in storage for a year now which actually allows the beans to stabilize. When we dry coffee we bring it down to a 10-12% humidity - so there is still water inside this bean. Usually products with a certain level of humidity will spoil quicker over time, but when natural coffees are stored with their skin their flavor profiles can actually enhance over time.
With naturally processed coffees you can expect really fruity and sweet notes often times accompanied by notes of wine or champagne.
