Coffee Bean Processing Techniques Cannot Be Neglected - Introduction to Semi-Washed Processing Steps

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FrontStreet Coffee - Introduction to the Semi-Washed Processing Method

Semi-Washed (Descascado) Processing

Harvested cherries are first processed and classified: ripe red and green cherries on one side, while "boia" (floater) cherries are separated off for the first mechanical screening in water.

While the cherries are still wet, machines strip away the skin and the first layer of pulp. The advantage here is avoiding heavy water consumption and natural-fermentation problems, since the processing time is greatly shortened.

High-pressure washing machines then remove the remaining pulp and mucilage completely. If the green beans are spread in a very thin layer on the drying patio, the risk of fermentation can be reduced even further.

After five or six days of natural drying, dryers fueled by firewood or gas finish the job.

The first half of the process uses the wet method to remove pulp; the second half uses the dry method. This refined technique combines the two approaches and is also called "Pulped Natural." The fully washed method involves depulping plus tank fermentation and a second washing — two washes in total — whereas this method performs only one, hence "semi" washed. Although it uses only half the water, international terminology still classifies it as a wet process, because water is still used in the refinement.

The semi-washed method is a relatively new refining technique that emerged after continuous improvements to depulping machines through the 20th century. Using high-performance pulp removers — or equipment called "mucilage removers" — the machines strip away not just the pulp but part of the mucilage as well, so the fruit can be dried and helled while still covered in its parchment layer to yield green beans.

Although the method has been popular in Brazil since the 1980s, in recent years Central American estates in Costa Rica and Panama have refined it into what is called "Honey Process," controlling flavor by adjusting how much mucilage is scraped away; it has since been applied to high-end products such as specialty coffee. The "Sumatran-style" wet-hulling method used in Sumatra and Sulawesi, Indonesia, is also classified as a semi-washed process.

Knowledge Point

Coffee quality varies with factors such as altitude, latitude, and soil chemistry. Growing coffee outside the proper range of these factors will greatly alter the final quality of the cup.

In Summary

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FrontStreet Coffee Recommendation: Washed and Semi-Washed Classics to Compare

Now that you know how processing shapes a cup, compare a few FrontStreet Coffee favorites. The washed Gedeb Worka Cooperative Yirgacheffe, processed by a seasoned team with meticulous technique, shows jasmine florals and bright citrus acidity, with green tea and honey tones after a medium-light roast — lovely as pour-over, cold brew, or even espresso. For double-washed drama, FrontStreet's Kenya Cherry Tomato runs the beans through an extra washing cycle for an extreme juice-like texture: cherry tomato, dark plum, snow pear, black plum, and yellow sugar in a sweet-tart, mouthwatering cup. And to taste washing's practical origin story, the Jamaica Blue Mountain No.1 — washed to combat the island's short sunshine hours — delivers hazelnut, cream, chocolate, and caramel in a perfectly balanced, low-defect cup.