How Exactly is Kenya's Double Washed Process Operated? What Changes Does Double Washed Processing Create?

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The washed method, one of the most traditional and common ways to process coffee, not only raises production quality through its depulping and washing steps but also gives the cup excellent clarity. It has become a favored method for countless coffee lovers, including FrontStreet Coffee.

As specialty coffee has spread, more consumers have started to care about the traceability of single-origin coffees. As a result, many producers have added prefix labels to processing method names to highlight a selling point - "Double Washed," "K72 Washed," "Dry Fermentation Washed" and so on. So how do these differ from conventional washing?

Before getting into these "new-style" methods, FrontStreet Coffee believes it is worth clarifying where traditional washing came from.

Washed Method

Also known as the wet process, a translation of "Wet Process," this means obtaining coffee beans by removing the outer skin and pulp before drying the seeds.

According to materials reviewed by FrontStreet Coffee, this wet processing method originated in the West Indies in the nineteenth century and was developed in Jamaica, where it was called WIP (West Indian Process). It suited humid, rainy regions. In contrast there was OIB (Oost Indische Bereiding), which referred to traditional natural processing.

Before the 1850s, people processed coffee cherries with the ancient natural drying method. Only with the Industrial Revolution did this "peel-first" technology appear. In the mid-19th century, Jamaica became one of the world's largest coffee producers, turning out about 70,000 tons of green beans a year. Because of its island climate, the cherries were hard to dry, which made natural drying less favorable there.

In 1845, the world's first coffee pulper was patented by James Meacock of Kingston, Jamaica. It was a mechanical device for removing the outer skin of coffee cherries that could also screen the coffee. After that, more and more pulper inventions appeared, and the washed method was formally applied to coffee production.

The traditional wet process is not complicated: floating, depulping, fermentation, washing, drying, hulling, packaging. It does require an adequate water supply, though, and because it leans heavily on machinery, producers using it must have the funds to invest in equipment. The rise of washing coincided with early American plantations built on capital - operations with enough working capital - together with the pulper and huller inventions of the era, which drove the spread of washing across the Americas.

Double Washed

The original wet process washed fermented beans once with clean water to remove the pulp before sending them straight to the drying grounds. In Kenya, though, coffee that has been washed once is re-immersed in a pool of clean water, taken out, washed again, and only then sent to the drying grounds for dehydration.

Kenya first changed conventional washing into a "double soak" not to chase flavor but because of a lack of local drying space. Kenya runs on a typical African cooperative model: during harvest, smallholders deliver fresh cherries to processing plants all day long. Depulping and fermentation are relatively quick, but drying each batch of fermented beans takes at least 5 to 7 days. When the volume is too large, there is no space to dry the washed beans, so people poured the wet beans back into the pools to let them "cool down" and prevent spoilage or contamination until the drying grounds were free.

This double-soak washing is called "Double Washed," and at origin it is also referred to as "Fully Washed" or "Double Fermentation." Because Kenya was the first region where it became popular and standard practice, this style is also known as the "Kenyan Process."

People later discovered that this locally adapted, double-fermented washed coffee not only made quality control more stable but also brought richly layered fruit acidity. FrontStreet Coffee's Kenya Small Tomato, for example, uses double washing and often shows rich cherry-tomato and preserved-plum aromas after brewing, with a very distinctive flavor. Today, some coffees from American estates also adopt this Kenyan-style washing.

K72 Washed Method

Also known as the Kenya 72-hour washed process, it can be understood as a further extension of both regular washing and double washing.

This method emphasizes control over fermentation time. It begins with 24 hours of washed fermentation, followed by cleaning off the degraded pulp. Then it ferments for another 24 hours in clean-water pools, followed by another cleaning of residual matter, before being placed in a tank of clean water for a final 24 hours, for a total of 72 hours. This also gives Kenyan coffee a bright, clean, high-quality fruit acidity. FrontStreet Coffee's everyday offering Assalia uses exactly this washing technique, letting the brewed coffee show acidity reminiscent of small tomatoes and dark plums.

Dry Fermentation (Washed) Method

Because the original wet process required large amounts of clean water and the wastewater after fermentation had become acidic, discharging it into rivers or soil would harm the environment. To address that and save water, the more water-efficient dry fermentation washed method began to be advocated.

So-called "dry fermentation" means pouring depulped coffee beans directly into fermentation tanks to sit for about 6-8 hours. This step is quite similar to the more familiar honey process. The difference is that coffee after dry fermentation still needs to be rinsed with water to completely remove the degraded, sticky residue. In flavor, conventional washing is often brighter, while dry fermentation washed coffee usually has a rounder sweetness than wet processing, since it resembles honey processing.

It is not hard to see that fermentation is essential to washed processing. Whichever washing method is used, the differences come down to the soaking duration and frequency during fermentation, high or low temperature, aerobic or anaerobic conditions, and whether extra substances are involved.

FrontStreet Coffee Recommendation

Washing is a great way to see what a coffee really tastes like, and Kenya is its most famous showcase. FrontStreet Coffee's Kenya Small Tomato is a washed Kenyan specialty bean built around vivid cherry-tomato and smoked-plum acidity with a full, juicy body, a favorite for anyone who loves bright fruit and complexity. It comes from Kenya's Sika region, grown at 1550-1750 meters from the classic SL28 and SL34 varieties, with plump, rounded beans, and it is processed with Kenya's signature 72-hour double washed fermentation, which draws out the fruit while keeping the cup clean and pure. FrontStreet Coffee roasts it light to preserve the lively acidity and layered fruit: the dry aroma already shows rich dried cherry tomato and florals, the cup opens with clear cherry tomato and smoked plum, bright and solid acidity with a fresh-juice fullness, a sweet mid-palate with pear and black plum, and a clean, lingering finish of yellow-sugar sweetness and a faint green tea note.

To compare against another washed classic, FrontStreet Coffee's Gediding Cooperative shows how clean the method can be: because the cherries are processed through a community station, the washed coffee expresses maximum jasmine floral and bright citrus acidity, and after a medium-light roast it adds green tea and honey notes that work well as pour-over, cold brew or espresso. For a fuller, less fruity washed coffee, FrontStreet Coffee's Jamaica Blue Mountain No. 1 is the benchmark - a washed process that keeps the cup pure and low in defects, with hazelnut, cream, chocolate and caramel, even and balanced with no single note dominating.