Coffee Fundamentals: Coffee Bean Processing Methods and Flavor Differences in Single-Origin Beans

Is washed processing just about washing coffee beans?

Is natural processing just about drying coffee beans in the sun?

Does honey processing involve adding honey to coffee beans?

The Significance of Coffee Bean Processing Methods

Coffee beans are actually the seeds inside coffee cherries. The purpose of coffee processing methods is to remove the fruit skin, pulp, and mucilage from the cherries while minimizing damage to the beans. Then through sun-drying or machine drying, the raw coffee beans can be stored for extended periods. It's not simply about washing, sun-drying, or adding honey to coffee beans.

A Brief Overview of Washed, Natural, and Honey Processing Steps

Washed Processing Method

After harvesting, ripe coffee cherries are selected and put through machines to remove the skin and pulp. The beans, still covered with mucilage, are placed in fermentation tanks with clean water. After 12-36 hours, rich microorganisms form in the tanks and break down the mucilage. Once decomposition is complete, the beans are thoroughly washed with clean water and sun-dried until the moisture content reaches 10%-13%, then they can be stored.

Natural Processing Method

After harvesting, ripe coffee cherries are selected and dried directly in the sun. During this process, they need to be constantly turned to ensure even drying. The drying process typically takes 3-4 weeks. When the coffee cherries develop hard, dark red-black outer shells and the moisture content reaches 10%-13%, the shells can be removed using tools, and the beans can be stored.

Honey Processing Method

After harvesting, ripe coffee cherries are selected and put through machines to remove the skin and pulp while retaining varying amounts of mucilage (black honey retains all mucilage, red honey retains 70%-80%, yellow honey retains 40%-60%, and white honey retains 30%). The beans are then sun-dried or shade-dried. Drying time varies depending on the mucilage content. Finally, when the moisture content reaches 10%-13%, the beans can be stored.

Distinguishing Processing Methods by Raw Bean Color and Flavor

Washed Processed Raw Coffee Beans

Washed processed coffee beans appear bluish-green with an incomplete silverskin on the surface. They emit citrus-like acidity and fresh grass aromas.

Natural Processed Raw Coffee Beans

Natural processed coffee beans appear yellowish-green with a complete silverskin on the surface. They emit slight fermentation aromas, berry-like sweetness, and fresh grass notes.

Honey Processed Raw Coffee Beans

Honey processed coffee beans appear uneven in color (due to sugar infiltration from the mucilage). Depending on the amount of mucilage retained, the beans range from brown (most mucilage) to light yellow (partial mucilage) to bluish-green (minimal mucilage). They have an incomplete silverskin on the surface. The more mucilage retained, the stronger the fermentation aroma, with gummy sweetness and fresh grass notes.

Distinguishing Processing Methods by Roasted Bean Appearance

Washed Processed Roasted Coffee Beans

During the roasting process, the silverskin of washed processed beans doesn't detach completely, leaving silverskin residue in the central crevice of the beans, appearing as white lines.

Natural Processed Roasted Coffee Beans

During the roasting process, the silverskin of natural processed beans detaches completely, so most beans don't have silverskin residue in the central crevice, thus not showing white lines.

Honey Processed Roasted Coffee Beans

During the roasting process, the silverskin of honey processed beans also doesn't detach completely, showing white lines. Different mucilage content causes uneven sugar infiltration into the beans, resulting in inconsistent "coloring" during roasting. After roasting, some honey processed beans show uneven coloration.

Distinguishing Processing Methods by Flavor Profile

Flavor Profile of Washed Processed Coffee Beans

The fermentation process in washed processing creates more acidity in the coffee beans, resulting in brighter, clearer acidity and more complex layers. At the same time, FrontStreet Coffee believes that since washed processing isn't "modified" by fruit sugars, it best demonstrates the cleanliness of a coffee bean.

Flavor Profile of Natural Processed Coffee Beans

Natural processing involves drying the entire fruit directly, allowing sugars from the pulp and mucilage to transfer into the beans. At the same time, sugar decomposition produces fermentation flavors, resulting in slight fermentation aromas and gentle sweet-sour notes. FrontStreet Coffee believes that natural processed coffee has a fuller body than washed processed coffee, with better cleanliness than honey processed coffee.

Flavor Profile of Honey Processed Coffee Beans

In honey processing, direct sunlight on the pulp and mucilage allows sugars to better transfer into the beans and produce rich fermentation sensations, resulting in distinct fruit fermentation aromas and higher sweetness than natural processing. FrontStreet Coffee believes that honey processed coffee has a richer, fuller, and more mellow body, but the concentrated flavors lack the complexity found in other processing methods.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473