Washed Processing: Pros and Cons, Characteristics of Washed Coffee Processing, Kenya Washed Processing

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Harvested coffee beans must immediately enter processing procedures, otherwise they will begin to ferment and develop off-flavors. The main processing methods are "natural process" and "washed process," which create different flavor profiles. Natural process beans have complete natural richness, gentle aromas, and more body; washed process offers good richness, high aromatics, and lively acidity.

Coffee cherries are composed of several layers from outside to inside: exocarp, pulp, mucilage, parchment, silver skin, and coffee embryo. Therefore, coffee beans undergo various processing methods before becoming green beans for export.

Washed Process

Green beans processed using the washed method have clear and smooth characteristics, mild aromas, and no off-flavors. Coffee beans from Central and South America are primarily processed using this method.

This method uses water washing and fermentation to remove the skin, pulp, and mucilage. Farms using the washed process must build washing pools and have access to continuous fresh water. During processing, fermented beans are placed in the pools and moved back and forth, using the friction between beans and the power of flowing water to wash the coffee beans until they are smooth and clean. After washing, the coffee beans are still enclosed in their parchment with a moisture content of 50%. They must be dried to reduce moisture content to 12%, otherwise they will continue to ferment and become moldy and spoiled. The better processing method is sun-drying, which is complex and time-consuming (taking 1-3 weeks), but produces excellent flavors that are highly appreciated.

Steps: Sorting floaters, removing skin and pulp (keeping mucilage layer), fermentation, washing, drying, hulling, grading and sorting.

Green beans processed using the washed method have approximately 12% moisture content.

The washed process has higher costs. To obtain 200g of green beans using the washed method, you need to process 1kg of coffee cherries and consume 10 liters of water, making it expensive.

Kenya Process

Following the initial steps of the general washed process, the beans first undergo natural fermentation for 12 hours (mainly at pH 4.5-4.8), then 80-90% of the mucilage layer is washed away, followed by another 24 hours of natural fermentation. After thorough cleaning, the beans are soaked in water for 24 hours before drying and storage. The fermentation and resting time for general washed processing varies from 12-24 hours, while Kenya soaks the green beans for 48-72 hours, which is why their processing method is commonly identified as the Kenya Process. Kenya's unique double-fermentation washed process further enhances the original acidity and cleanliness, resulting in rich berry notes, solid body, high sweetness, and lively acidity.

Taking FrontStreet Coffee's Kenya Asali as an example, the K72 refined washed processing brings bright fruit acidity and rich berry aromas to this bean.

FrontStreet Coffee recommended brewing parameters:

V60/90°C/1:15 ratio/Time: 2'10"

Flavor: Rich cherry tomato and blackberry flavors, with brown sugar and cane sugar sweetness.

Important Notice :

前街咖啡 FrontStreet Coffee has moved to new addredd:

FrontStreet Coffee Address: 315,Donghua East Road,GuangZhou

Tel:020 38364473