Ethiopia Lake Abaya vs. Natural Ethiopia Lake Abaya. Natural Sumatra Wahana vs. Sumatra Mandheling. The difference? How the coffee beans were processed. We're not talking the different processes for decaffeination, but how the fruit of the coffee plant, the coffee cherries, are turned into roastable green coffee beans. Natural, washed, honey processed, wet hulled, are all names for different ways to process coffee cherries into coffee beans.
The oldest form of processing is “Natural,” or “Dry Processed.” After they're picked, coffee cherries are laid out on screens to dry. In some cases, they're left to dry on the plant. Once the red fruit has dried to a brown or black (like raisins), the dried fruit is scraped off. Under it is a parchment shell, and inside that are the green coffee beans. The parchment is “milled” off the beans and voila, naturally processed coffee. Almost all lower quality coffees are naturally processed, as are many specialty grade coffees from Brazil, Africa, and Indonesia.
“Washed” or “Wet Processed” coffee is not any less natural, but the process is more complicated and uses a lot more water. The coffee cherries are soaked it water until the fruit softens and ferments. Then more water is used to wash the fruit from the parchment. The parchment covered beans are then laid out on screens to dry. Most high quality Central American and South American coffees are “Washed,” as are many exceptional Africans. This is the process least likely to find its way in a coffee's name.
Other coffees use hybrids of these two processes. Look for names that include, “Wet Hulled,” “Mandheling,” “Giling Basah,” “Honey Processed" or "Pulp Natural.” In a Mandheling, or wet hulled process, the coffee cherries sit for about a day before the fruit is washed off the parchment. The coffee beans are then milled from the parchment before they are spread out and dried. This is a much faster process and works better for places where growers can't count on long, sunny days to dry their coffee. In "honey processed," or "pulp natural," the skin and some of the fruit, but not all, is scraped off before the drying stage. Many Indonesian coffees are wet hulled while honey processing is becoming popular with some Central American coffees.
Does process matter? In terms of flavor, absolutely! Washed coffees tend to have a clean coffee flavor, with more lively notes, and a relatively light body. Natural and honey processed coffees keep aspects of the dried fruit, making for a more complex flavor and heavier body. Wet hulled coffees have the heaviest body of all, but because of the hazards of drying the coffee beans without the parchment shell (for instance, fungal or bacterial infections or contamination from foreign bodies) the coffee may have a funky, earthy flavor. The highest quality wet hulled coffees, though, have deep dried fruit and/or bakers chocolate notes with a very heavy, almost syrupy body and hold a very special place among the best coffees in the world.
Next time on What's in a Name? The Buzz on Caffeine.