The coffee process involves a series of steps that go from the coffee plant and into your cup. In this week’s post, you’ll learn about the three most common types of post-harvest processing methods used by coffee producers around the world, so that you’ll have a clear understanding of what we mean when we say things like natural gesha, honey processed bourbon or washed caturra.
What is Coffee Processing?
Post-harvest processing is the stage of the coffee process in which producers remove the outer layers of the coffee cherry to expose the green coffee beans that we then roast. There are a number of different processing methods, but the most common are natural (dry), washed (wet) and honey processing.
Processing has a great impact on bean quality, which is why Sam, our Head Roaster, always takes processing into account when curating the beans for our signature blends and single origin coffees.
The simplest and oldest way to process coffee is natural processing, also known as dry processing. In this method, the whole cherry – with its pulp, mucilage, husk and all – is dried in the sun or in industrial tumble driers, right after being harvested. If sun dried, the process can take up to four weeks, and a fair amount of fermenting occurs in the fruit during this time.
After cherries are dry enough, they are hulled in a machine to remove all the layers that cover the green coffee bean.
A downside to natural processing is that there’s not much room to improve bean quality, because the only variables you can tweak are how ripe the cherries are when harvested, and the overall time to dry.
In the wet method, before the beans are dried, the outer skin or pulp of the coffee cherries is first removed with a machine called a depulper. Afterwards, the depulped beans are fermented for 12 to 48 hours in large tanks of water. During this fermentation, different bacteria, yeasts and fungi break down the sugars and other compounds in the mucilage (a sweet, thick, sticky layer that covers the parchment) making it softer and easier to remove.
After fermenting the beans, the softened mucilage is finally removed by “washing” them with large amounts of water. As a consequence these beans are called Washed Coffee Beans.
Honey Processed Coffee
Honey processing is middle ground between natural and washed processing. This method, which originated in Brazil in the 1950’s, starts by pulping the fruits just like in the wet process, and then sun drying them with all or a part of the mucilage still on the parchment.
The sweetness and stickiness of the mucilage during drying earned these beans the name Honey Coffee.
There are three degrees of honey processing depending on how much mucilage is left on the beans before drying.
Yellow Honey implies removal of a good portion of mucilage with mechanical equipment and then sun drying for 8 – 10 days.
Red Honey, where producers only remove 25-50% of the mucilage and then they sundry the beans for 12-15 days
Black Honey, where the beans are dried with all the mucilage for up to 30 days.
The flavor profile of Honey coffee beans reminds you of naturals, which is why they are also called Pulped naturals.
How do the different processing methods affect Flavor Profile?
Processing has a great impact on bean and cup quality. Here are the most relevant flavor notes you can expect from the different processed coffee beans.
-Sweet, smooth and complex attributes.
Shares many of the flavor notes of naturals, but lacks the unwanted harsh notes of green or unripe cherries that are usually present in many naturals with uneven ripening
There are numerous other processing methods, some of which are still experimental, and others that have become famous for their innovation. In our next post in the coffee processing series, we’ll explore the exotic world of Animal Processing, like in Kopi Luwak or in Elephant coffee.
Please enter a valid email address
Thank you for your subscription!