Popular articles
Recent discussions on forum
Coffee Processing Methods
What Are They and How Do They Affect the Flavor?
Published September 10, 2021
Susan Rov
Coffee experts@The Coffee Lab
Adequate brewing equipment, technique, and skill will help you to prepare a delicious coffee. But most of the flavor has been concentrated in the bean long before you even start brewing.
Knowing what the single origin of a coffee is can be a good first indicator of what you can expect from your cup. But it doesn’t stop there. The flavor is further determined by varietal, elevation, roast, and processing method—in other words, the way the coffee cherry processes from the seed to a bean ready for roasting.
There are three main processing methods used by coffee farmers around the world. This article will explain the meaning behind washed, natural, and honey processes, as well as look at how they affect the flavor of the final cup.
What Is a Coffee Processing Method?
A coffee cherry contains two seeds that are surrounded by mesocarp and mucilage layer. The processing method signifies the technique in which these layers of pulp are removed from the bean.
These methods alter the chemical composition of the green beans, can add sweetness, affect the body, and increase acidity.
It is one of the most crucial stages that the bean undertakes before it makes its way into your cup. Even when harvesting the ripest coffee cherries, if the processing method goes wrong, it can lead to terrible-tasting coffee.
There are three main processing methods used worldwide: washed, natural, and honey. The choice of which depends on different traditions, innovations, and conditions of the origin country.
Washed or Wet Processing Method
This is the most common method, with around 50% of the coffee produced in the world undergoing this process.
It starts by removing mucilage and the outer layer of the cherry before drying, the process also known as depulping.
Then, the coffee beans are placed in fermentation tanks. During this stage, the inferior, less dense beans float on the surface and are removed. The good cherries sink and are left in the fermentation tank for at least 12 hours, the time of which is determined by the climate and altitude.
After the fermentation, leftover flesh is removed and beans are dried. The wet fermentation results in a clean, bright, and crisp flavor.
Alternately, coffee can also undergo a dry fermentation process, where the fruit is washed and placed in the sun to dry. This is a riskier process that results in a slightly fuller body and sweeter complexity.
The washed processing method is highly regarded and sought after in the coffee world. It is a more stable process than natural processing, which results in less risky flavors but also demands more money and resources from the farmers.
How Does It Affect Taste?
When tasting coffee that has undergone a wet processing method, expect clean and bright flavors, a well-balanced body, higher acidity, and an aromatic finish.
The tasting notes can range depending on the origin and varietal but in general, this coffee displays citrusy and fruity flavors, with floral delicate undertones and a silky body. The washed processing method can also reveal darker deep chocolate flavors.
Washed coffees have a brighter, more nuanced profile which is what makes them desired by most coffee drinkers. The countries where washed processing dominates are Latin America and Africa.
Natural or Dry Processing Method
During natural processing methods, the entire bean with mucilage and skin is left intact and then laid on patios or sunbeds, where it’s left to dry until reaching a certain level of moisture.
The producers can change variables that can speed up or slow down the process, such as the thickness of the layers or levels of shade.
Once the fruit becomes hard, machines are used to crack through the fruit layer. Since the pulp and skin are left on the surface of the bean, it absorbs more characteristics from the fruit than wet-processed coffee.
This process comes with a certain stigma and divides the coffee crowd into people who love naturally processed coffee and the ones who think this is an inferior process.
This stigma comes from the fact that in the past, the natural processing method was used for leftover coffee that wasn’t suitable for export, to prevent wasting time and money on the extra steps.
In recent years, the specialty coffee world started to recognize the high-quality potential of naturally processed coffee. But the fact remains that this is a riskier process with less margin for error, which can produce off-flavors.
How Does It Affect Taste?
The flavors of the naturally processed coffee are easy to recognize. They have a fuller body, intense flavors, and fruity tasting notes inherited from the pulp. They are diverse, bold, with a heavier body but they can also include more delicate flavors of tropical fruit, bergamot, or dry chocolate.
Generally, the flavors of naturally processed coffee are wilder and display less clarity. The acidity is less common and more intense. Occasionally, they can also develop funky alcohol-like flavors and leave a chalky lingering taste on your tongue.
The natural process is common in Ethiopia and Brazil, where there is no access to water. It is also the method with the oldest tradition.
Honey or Pulp-natural Processing Method
Honey and semi-washed processing methods are very similar, and they sit somewhere between the washed and natural processes.
They include depulping the cherry after harvest, just like washed process, but they skip the fermentation in water tanks and leave the leftover mucilage to dry with the seed.
The difference between the honey and pulp-natural processes is that the semi-washed process uses water flow to remove mucilage, while the honey process uses the dry depulping technique without water.
With these methods, some of the sticky fruit still remains on the surface of the bean when it is placed on beds for drying. However, since there is less flesh left, the risk of over-fermentation is lower.
The honey processes are categorized by color, according to the amount of flesh left on the bean. The categories are black, red, yellow, and white honey, with the black honey process having the biggest amount of flesh left on the bean.
How Does It Affect Taste?
In terms of flavor, this method represents somewhat of a middle-ground between the washed and the natural processed coffee.
The process is less risky and wild than naturally-processed coffee and has more flavor than wet-processed beans. The coffee displays the sweetness from the bean as well as the brightness of the washed coffee.
The coffees have muted acidity and approachable, jammy, and sugary notes, plus a creamy body with a texture and taste resembling honey.
The flavors can range from berry to citrusy undertones, including the taste of plums, cherries, hazelnuts, and almonds.
This processing method is often used in Brazil, El Salvador, and the rest of Central America.
What is your preference? Do you look for bright cups of washed coffees or are you seeking the original flavors of naturally processed beans? Next time you get a bag of beans, pay attention to how these methods affected the flavor.
About the author
Susan Rov
A retired barista who turned into a writer. I love discovering coffee flavors and learning more about the magic bean.
Add comment
More on the coffee lab
Sign up and contribute now