Coffee Processing Methods Explained

As artisans of coffee, we are committed to understanding the complete lifecycle of coffee beans. From the moment the coffee cherries are plucked to the final sip in your cup, there is a fascinating process that shapes coffee’s character and quality. In this Gateway article, we will explore the various coffee processing methods, revealing the science and craftsmanship that make each cup a truly unique experience. 

Washed (Wet)

Washed processing, also known as the wet process, is one of the most common methods used in the coffee industry. Freshly harvested coffee cherries are pulped to completely remove the outer skin and mucilage. The beans are fermented in water before being thoroughly washed and dried. As a result, washed coffee showcases pure intrinsic flavours from the beans itself, producing a clean and bright cup that highlights the unique characteristics of the coffee bean.

Characteristics: Bright and vibrant fruity flavours with higher acidity.

Natural (Dry)

In contrast to the washed process, the natural process involves drying the whole coffee cherries in the sun while still retaining its outer skin and mucilage. As they dry, the fruit naturally ferments and imparts unique, fruity flavours to the beans.

Characteristics: Intense, fruity flavours with enhanced body and sweetness.

Honey (Pulped Natural)

Honey processing is a hybrid method that falls between the washed and natural processes. A portion of the coffee cherry, such as the skin and some parts of the mucilage is removed before drying and the remaining layers are removed afterwards. The amount of mucilage left on the beans varies, which creates a spectrum of honey processing types: yellow, red, and black. Each type adds a different dimension to the final cup.

Characteristics: Enhanced sweetness and body.

Semi Washed

Semi washed combines elements of both washed and natural processes. The outer skin of the cherry is removed using a pulping machine, leaving the mucilage covering the beans. The beans are then spread out to dry in the sun or with mechanical dryers. The mucilage ferments during drying and imparts some of its sugars and flavours to the beans. 

Characteristics: Balanced and smooth body with fruity notes.

Wet Hulled (Giling Basah)

In wet hulled processing, ripe cherries are depulped and fermented overnight to break down the mucilage. After that, the beans are thoroughly washed and allowed to air-dry for a few hours until their moisture content reaches around 30-40 percent. Finally, the parchment layer will be mechanically removed to complete the process.

Characteristics: Distinct earthy, spicy, and full bodied flavour with low acidity.

Anaerobic Fermentation

Anaerobic refers to the lack of oxygen. This process involves depulping coffee cherries and sealing them in airtight containers to prevent oxygen from interacting with the beans during fermentation. This encourages unique microbial fermentation that leads to complex and unique flavour profiles.

Characteristics: Exotic notes with pronounced acidity and fruity or floral notes.

Carbonic Maceration

Carbonic maceration is an anaerobic fermentation process that introduces Carbon Dioxide (CO2) into the sealed tanks to create a controlled fermentation. The CO2 helps create a unique fermentation environment that affects the beans’ chemical reactions during fermentation. 

Characteristics: Bright acidity, floral notes, and winey or fruity flavours.

Each coffee processing method has its unique attributes and impacts on the flavour, aroma, and characteristics of the coffee beans. At Terminal 3 Coffee Roasters, we appreciate the artistry that goes into selecting the right processing method to bring out the best in every coffee bean. Whether you prefer the clean, bright notes of washed coffee or the intense, fruity flavours of a natural, there's a coffee for every palette.

So, the next time you enjoy a cup of coffee, take a moment to appreciate the journey from the coffee farm to your cup. Remember that it’s not just a beverage; it’s a journey, a craft, and a passion.