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The present invention discloses a machine for washing coffee to which the mucilage has been previously degraded by fermentation. The machine of the present invention comprises: a pulping system; a continuous conveying system for conveying the pulped coffee to a device for sorting by size, in which a large part of the pulp and unpulped fruits are removed; a continuous conveying system for conveying pulped coffee to the cylindrical fermentation tanks; one or more cylindrical tanks to permit their discharge by gravity and facilitate subsequent washing to deposit the pulped coffee and permit the degradation of the mucilage; a worm screw to feed the coffee with degraded mucilage in doses from the tanks to the mechanical washer; a mechanical washer with a vertical upward flow of beans, consisting of a rotor with a series of agitators in conjunction with worm screws, one located at the lower base of the rotor and the other located in the upper third of the rotor. The honeys produced from the washing in the present invention are not mixed with the pulp, they can be dehydrated and subsequently added to the decomposed pulp, using solar energy or any type of dryer, in order to avoid the generation of leachates and to achieve 100% control of the water pollution generated in the process. The method disclosed in the present invention consists of: Pulping the coffee fruits; transporting the coffee to a separation system to remove the fruits that are not pulped and a large part of the pulp; transporting the pulped fruits to a tank storing in the tanks the pulped fruits allowing the degradation of the mucilage either with natural fermentation or using pectinolytic enzymes; transporting the coffee from the fermentation tank to the mechanical washer; removing the degraded mucilage, allowing to obtain washed coffee ready to start the drying stage.