What is K72 Washed Processing Method? What are Washed Process Coffee Beans?

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The washed process is one of the most traditional and most common ways of processing green coffee. Removing the parchment and washing the beans not only lifts production quality dramatically but also gives the brewed cup excellent clarity — which is why it is a favourite method among countless coffee enthusiasts, FrontStreet Coffee included.

As specialty coffee has spread, more consumers have started paying attention to the traceability of single-origin coffee. To make certain selling points stand out, many producers now attach prefixes to processing names: "double washed," "K72 washed," "dry fermented washed" and so on. So how do these differ from conventional washing?

Before getting into these newer methods, FrontStreet Coffee thinks it is worth sorting out where traditional washing actually came from.

Washed Process

Also called wet processing, a translation of "Wet Process," this is a way of producing green coffee in which the skin and pulp are removed before the seeds are dried.

According to the material FrontStreet Coffee has reviewed, this wet method began in the West Indies in the nineteenth century and was developed in Jamaica, where it was known as WIP (West Indian Process). It suited humid, rainy regions. The counterpart was OIB (Oost Indische Bereiding), which referred to traditional natural processing.

Before the 1850s, people processed coffee cherries with the oldest method of all: drying them in the sun. It took the Industrial Revolution for this peel-first technology to appear. By the mid-nineteenth century Jamaica had become one of the world's largest coffee-producing countries, turning out roughly 70,000 tons of green beans a year. Its island climate, however, made cherries hard to dry, so natural drying was simply not favourable on that land.

In 1845 the world's first coffee pulper was patented by James Meacock of Kingston, Jamaica. It removed the outer skin of the coffee cherry and could also screen the beans. More pulper inventions followed, and the washed process was formally put to work in coffee production.

Traditional wet processing is not complicated: floating → pulping → fermentation → washing → drying → hulling → packaging. Carrying it out, though, demands an adequate water supply, and because it leans heavily on machinery, producers who wash coffee also need enough capital to buy equipment. The rise of washed coffee coincided with early American plantations backed by capital, which had operating funds to spare; together with the pulpers and hullers invented to meet the demands of the age, that is how washing spread through the Americas.

Double Washed

In the original wet process, fermented beans were washed once with clean water to remove the pulp, then taken straight to the drying yard to dry and be packed. In Kenya, coffee that has been washed once is immersed again in a pool of clean water, taken out, washed a second time, and only then sent to the drying yard to shed moisture.

Kenya's reason for turning conventional washing into a second immersion was not flavour at all — it was a shortage of drying space. Kenya runs on the typical African cooperative model: during harvest, smallholders deliver fresh cherries to the processing plant all day long. Pulping and fermenting are relatively quick, but drying each batch of fermented beans takes at least 5 to 7 days. When the volume arriving is simply too large, there is nowhere to dry the washed beans, so people poured the wet beans back into the pool to "cool down" and avoid spoilage or contamination until drying space opened up.

This form of washing, with two soaking periods, is called "Double Washed," and at origin it also goes by "Fully Washed" or "Double Fermentation," meaning completely washed. Because Kenya was the first region where the method became popular and was put into practice, this style of washing is also called the "Kenyan Process."

Later, people discovered that this twice-fermented washed coffee, born of local conditions, did more than keep production quality stable — it also brought rich, layered fruit acidity to the cup. FrontStreet Coffee's Kenya Small Tomato, for example, uses double washing and often shows abundant cherry tomato and preserved plum aromas once brewed, with a very distinctive flavour. Some American estate coffees are now processed in this Kenyan style too.

K72 Washed Process

This refers to the Kenya 72-hour washed method, which can be understood as a further extension of both regular washing and double washing.

The emphasis here is control over fermentation time. It begins with 24 hours of washed fermentation, after which the loosened pulp is cleaned off. The beans then ferment for another 24 hours in a clean water tank, followed by another round of cleaning to remove residual material, and finally go into a tank of clean water for the last 24 hours of fermentation — 72 hours in total. The method gives Kenyan coffee a bright, clean, high-quality fruit acidity. FrontStreet Coffee's everyday offering Assalia is washed this way, and the brewed cup shows acidity reminiscent of small tomatoes and smoked plums.

Dry Fermentation (Washed) Process

Because the original wet process required large amounts of clean water and the wastewater left after fermentation was acidified, discharging it into rivers or onto soil harmed the environment. In response to environmental protection and water conservation, the far more water-efficient dry fermentation washed process came to be advocated.

What is called dry fermentation means pouring the parchment beans straight into fermentation tanks after the fruit skin is removed and letting them sit for about 6-8 hours. That step is actually very close to the honey processing people are more familiar with. The difference is that dry-fermented coffee still has to be rinsed with water to strip away the degraded, shed mucilage completely. In the cup, conventional washing is usually brighter, while dry-fermented washed coffee tends to have a rounder sweetness than wet processing, precisely because it resembles honey processing.

It is not hard to see that fermentation is essential to every washed process. Whichever washing method is used, the differences come down to how long and how often the beans soak during fermentation, whether the temperature is high or low, whether conditions are aerobic or anaerobic, and whether anything extra is added.

FrontStreet Coffee Recommendation

Washed coffee is prized for its clarity, and FrontStreet Kenya Small Tomato is the clearest illustration of it. Kenya is exceptionally good at double washing green coffee, and this lot repeats the washed step: float and soak the beans, wash the residual mucilage off the surface, soak them again, then dry, hull and store. All that repeated rinsing and soaking presents the juice character at its most intense — small tomato, smoked plum, snow pear, black plum and brown sugar, juicy and sweet-tart at once. It is a favourite of many coffee drinkers.

If you want the jasmine-and-citrus side of the washed world, FrontStreet Ethiopia Yirgacheffe Gutingting Cooperative is the other essential reference. Yirgacheffe is well known, but fewer people realize that small local yields mean farmers send their cherries to a cooperative for central processing. Gutingting is an excellent processing team from Gutingting village with seasoned technique, and it made its name on an especially refined, clean cup. The washed process lets jasmine florals and bright citrus acidity come through at maximum strength, and a light-to-medium roast adds green tea and honey notes. It works as pour-over, cold brew or espresso.

FrontStreet Jamaica Blue Mountain No.1 shows what washing does for a classic profile. Jamaica is an island climate with comparatively short sunlight hours, and to reduce the chance of beans spoiling, the washed process was developed there in the first place; its key difference from natural processing is that skin, pulp and mucilage are removed before drying, which cuts the water wrapped around the bean and shortens drying time. The result is translucent, low-defect green coffee. Washing is what guarantees this Blue Mountain's concentrated aroma — hazelnut, cream, chocolate and caramel in a pure expression, balanced so that no single note dominates or goes missing.