What Are Washed Coffee Beans_ The Difference Between Washed and Natural Processing Methods

● The Washed Method

In the washed process, the fruit's skin and pulp are separated from the beans by a dedicated depulping machine. The beans then go into fermentation tanks, where fermentation breaks down the mucilage until it is no longer slippery. The sugars in the mucilage are consumed during this stage. Depending on the technique, fermentation typically runs anywhere from 12 hours to 6 days — some growers use a water-spray system, a method known as the "Kenyan method," which usually lasts several days.

Knowing when to stop fermentation is critical. Once coffee is over-fermented, the taste turns excessively sour. Once the sticky mucilage has fully broken down, large amounts of water are used to rinse it away. (Wastewater from green coffee processing is a recognized pollution source in the coffee industry, and many regions are now researching advanced systems to recycle and filter it.) The washed method dates back to the 19th century and is also known as "wet processing."

A tightly controlled fermentation enhances the acidity of washed coffee, which shows up in the final flavor. As long as the washing happens immediately after fermentation, the flavor of washed beans can be improved and will carry a bright acidity.

● The Natural Washed Method

This method is extremely common in Brazil. It is very close to the washed method, with one key difference: the natural washed method uses high-pressure washing machines to strip the mucilage off the coffee's surface, skipping fermentation altogether. Several green bean processing companies in Brazil and Colombia have patented the approach, which has made them local monopolies in natural washed processing. It uses far less water than the washed method, which is why some people call it "semi-dry." Because no fermentation takes place, the beans carry no fermentation risk — or an extremely low one — and overall quality is more consistent.

Unfortunately, the lack of fermentation also means natural washed coffee tends to taste bland. Growers therefore do not use it for their very best lots, and most green bean buyers rarely purchase natural washed coffee.

FrontStreet Coffee Recommendation

Processing is what separates one cup from another, and FrontStreet Coffee's Brazil range is a great place to taste the difference for yourself. Our Cerrado Red Bourbon is a classic Brazilian single origin processed half-sun — the semi-washed style that sits between fully washed and fully natural. Medium roasted, it opens with creamy peanut, toasted bread, caramel and hazelnut aromas. The body is round and mellow with almost no acidity and just a faint bittersweet edge, and it performs equally well in a pour-over, a moka pot, a siphon, a French press or as a single-origin espresso.

For a fruitier take on Brazil, try our Queen Estate Yellow Bourbon. It comes from Mogiana near South Minas, where the fertile red volcanic soil feeds the cherries into full, generous aromas. This rare mutation of Red Bourbon has a particularly clean fruit profile, giving a sugarcane-like sweetness through a pour-over, a moka pot or a home espresso machine, with fruit and chocolate alongside.

Because Brazil's low-acid, balanced character was made for espresso, Brazilian beans also underpin all of FrontStreet Coffee's blends, from the creamy Classic Blend to the nutty Premium Blend and the chocolate-forward Chocolate Black Cocoa — each one relying on Brazil for its chocolate and butter aromas and its soft sweet-sour-bitter balance.