What Is Natural Processing

Natural or dry coffee processing is one of the oldest methods of processing coffees.  Once the cherries are picked from the tress, they're cleaned then spread out in the sun to dry on cement or raised tables.  They're left in the sun for weeks and are periodically raked and turned to ensure an even drying process and to prevent mildew growth.  Because the coffee is laid out in the sun for weeks, natural processing is only used in regions that have very little rainfall, little access to water, and long periods of sunshine.  Most coffees from Indonesia, Brazil, Yemen, and Ethiopia are dry processed.

african raised bed
Drying cherries on raised beds. Image © Ninety Plus, used with permission.

As the cherries dry, they darken in color and harden.  Once they've reach an appropriate dryness — a maximum of 12% — they are sent to a mill where they are hulled, sorted, graded and bagged for shipment.

Coffees that have been processed naturally are often sweeter and have more body and a more complex flavor and aroma profile.  This is most likely a cause of the fermentation process.

patio dried
Drying cherries on the ground, also known as patio drying. Image © Ninety Plus

Believe it or not, the processing method (dry, wet, or pulped, etc) is one of the single most important factors in a coffee's flavor, second only to picking appropriately-ripe cherries.  There are still debates about which process is best and countries like Brazil are moving aggressively to modernize and automate as much as possible.  What effects that modernization has on the flavor and quality of the coffee remains to be seen, but my concern is it will go the same route as other industrialized crops such as corn in the U.S.

Michael C. Wright

Michael is an American expat living in Singapore where he writes about many things coffee-related. A roaster by trade, Michael is also a licensed Q Grader and an Authorized SCA Trainer (AST).