How Coffee is Processed Around the World
One of the most charming aspects of any in-depth relationship with coffee is getting to know the beverage's nuances from country of origin to country of origin. But as romantic as it sounds to credit a coffee's terroir with its final flavor, how the coffee itself is processed after harvest accounts for a great deal of what you taste in the cup. We've already highlighted some countries in these pages with unique ways of processing coffee, like Sumatra, but what are some other methods of coffee processing that are closely tied to their countries of origin, that makes coffee from these countries likely to be different and special?
Read on for a glimpse into more of the world behind the scenes of your daily brew.
Ethiopian coffee has both a highly esteemed and divisive reputation. Those that undergo "natural" or "dry processing"—that is, they're set out to dry right after harvest with the coffee fruit and mucilage (that sticky layer just under the skin) still on the bean—are well known for their deeply sweet and fruity, full-bodied characteristics, reminiscent of a deep blueberry flavor. Once dried, the fruit and mucilage are then removed from around the coffee seed all at once.
The arguments against naturally processed coffees are that the process itself can carry with it a risk of overfermentation and negative impact on the bean itself, but in Ethiopia, where techniques like this have been in practice for longer than anywhere else, the results are likely to be delicious ones. "I think the reason natural coffees from Ethiopia are so good is that the coffee's so good already," said Gabe Boscana of Paramo Coffee in San Francisco. "They don't have a lot of rain, which is why naturals are really successful in Ethiopia. There's a lot of dry, steady, not super-hot heat&emdash;it's a temperate climate which I think helps them develop fairly clean naturals without a kind of ferment."
Coffee plants thrive in Kenya's sunny weather, and the dry climate also benefits its method of coffee processing. The flavorful coffees that originate in this country are often known for their acidity, juiciness, and complex red fruit flavors. Kenyan coffees are also traditionally known for what's called a "clean cup," which is a shorter way of expressing that a coffee has delicacy and defined flavors, without hint of ferment, funkiness, or the earthy notes that can come from defects or processing.
Why's this the case? Kenyan coffees are washed—a post-harvest process that takes place in many countries, but Kenya's coffee washing stations, or "coffee factories" as they are called there, are by and large cooperatively owned, allowing for tremendous consistency and a shared interest in quality.
Kenyan coffees are first de-pulped to remove the fruit from around the bean, then are fermented and washed—sometimes in more than one cycle of both—and soaked in water. The beans are then dried and rested on specially built raised beds. The result? Highly expressive, balanced, and often intensely citric and fruity flavors considered to represent some of the most realized potential in coffee production.
We've just compared countries who excel at natural processing and washed processing of coffee. Is it possible there's a happy medium somewhere in between? Costa Rica's unique "honey process" attempts to hit this mark.
Whereas in a washed coffee, where both fruit and mucilage are removed from the bean before it is fully dried, honey process—also called "pulp natural" and "semi-washed"—removes the skin of the fruit, but leaves some of the mucilage on the bean. The coffee is then set on patios or beds to dry with the mucilage still on, absorbing the naturally occurring sugars from the fruity mucilage—a sweetness you'll quickly testify to in the finished cup.
Depending on the technological abilities of an individual coffee mill, producers may even be able to attenuate the amount of mucilage left on the bean, which allows further control over the ultimate flavor. It can be risky, however—all those sticky beans can clump together, and drying them requires great care to rotate and monitor as a producer waits for the coffee to completely dry.
Honey process is a newer mode of handling coffee that's gained popularity in Brazil, Panama, and many other countries—but Costa Rica may be the country that's run the farthest with this ball. The Central American nation has different color-coded categories for how much mucilage is left on in the process, and have truly popularized the method to great success. "Once you roast it, it's precaramelized," says Boscana, a veteran coffee roaster. "When you throw it in the machine, you get this heavy sweetness that's coming from the sugars that dried around the coffee bean."
In Brazil, you'll find natural processed coffees as well as washed. But newer technology sets this country's coffee processing apart. The Brazilian coffee industry benefits (some might say) from the country's affluence in terms of producers' ability to mechanize stages of the process, and experiment with different technological solutions. Mechanical picking machines do the labor formerly performed by humans at some Brazilian farms, stripping coffee trees of varying levels of ripe cherries to be sorted out later by other machines. Some of these machines are more basic, sorting out overly mature coffee beans by floating them in water, and discarding too-firm underripe beans. Yet further machines can sort by color, removing labor intensive hand-sorting from the quality control process.
What does all this mean to the coffee drinker? Hopefully, lower prices on coffees (be they natural, honey, or washed processed) with the classic Brazilian characteristics of sweet, chocolatey, balanced soft flavors, often used as low notes in espresso blends.