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processing methods

Once the coffee berries are harvested, it goes through post-harvest processing where the pulp is removed from the beans. There are three main different ways that the farmers do this — natural, washed, and honey. Each method would yield a different level of flavor and aroma in the coffee that we drink.

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natural

Natural processing is the oldest method of processing coffee, and is best known for producing beans with a heavier body and more pronounced flavor. After picking the coffee cherries, they are spread out in thin layers to dry in the sun — without removing the fruit from the bean. Drying stations differ depending on the farm or region — most farmers though use special raised beds which enable air to flow around the cherries. The cherries are turned regularly to avoid any spoiling or rotting, and once they are are properly dried, the skin and dried fruit flesh are mechanically depulpled, exposing the green beans which are stored and “rested” before roasting.

This method is often used in parts of the world where there is very limited access to water and longer periods of sunshine. The natural process results in a very pronounced fruity flavor of coffee, with diverse flavor notes and a milder sip. 

washed

Also called the “wet” method, the coffee berries are put through a depulping machine to separate the beans from the fruit, and soaked in water for the fermentation process to remove the remainder of the fruit flesh. The amount of time that the fermentation requires depends on the climate and altitude. Usually the fermentation requires 24-72 hours and if the coffee beans are fermented for too long, it will have negative effect on the flavor of the coffee. The hotter the climate, the less time the beans will ferment.

Once fermented, the beans are washed again and then left to dry. Drying happens a few different ways, depending on the region – from raised beds or brick patios in the sun, turned regularly for even drying, to mechanically in areas where there is too much humidity or not enough sunlight.

Washed coffees depend almost 100% on the bean having absorbed enough natural sugars and nutrients during its growing cycle. The process leads to bright and acidic flavors. and It’s commonly appreciated by roasters and baristas because of the increased complexity and cleaner cup profiles.

honey

The honey process is a hybrid of the natural and the washed process. The bean is removed from the outer fruit, but leaving a certain amount of the mucilage on the bean during drying. The natural sugars from the remaining mucilage will sweeten the final product. 

There are different honey processes, depending on the amount of mucilage left on the bean.

White honey: 75-100% of mucilage removed

Yellow honey: 50-75% of mucilage removed

Red honey: 0-50% of mucilage removed

Black honey: minimum mucilage removed

Honey processed coffee often has the full body from a natural processed coffee, yet with the bright but well rounded acidic notes of washed coffees.