Wolichu Wachu is a washing station located in the Guji growing region of Oromia. It is part of the Harso Haru Mude Farmer Cooperative and services around 4500 smallholder producers. Wolichu Wachu is a new washing station that started operating in 2017. The advantage of being recently built is that its construction could integrate all new insights into coffee processing. Its layout corresponds to a maximum efficiency during processing and drying. The intake point lies at the top of a gentle hill. The depulping machine, fermentation tanks and washing channel lie a bit lower. This way, gravity carries the coffee through the process, without a need for pumps like with older washing stations. The spacious and well-organized drying field lies at the bottom of the station.
Processing at Wolichu Wachu
Wolichu Wachu is equipped with sorting tables to monitor the cherry quality at intake. The collection agent oversees the quality of the cherries before processing. For the washed coffees, an initial screening through flotation takes place during depulping. The depulper at Wolichu Wachu integrates this step into its processing chain right after it tears off the cherry skin. It shakes lights and floaters to the end of the machine into a different tank for separate processing. Next, the coffee ferments under water for 36 to 72 hours. In this period, the water is changed 3 times.
Once the mucilage has broken down sufficiently, the coffee is released into the washing channel for cleaning. During this step, the station’s staff pushes the coffee through channels. This separates the coffee in parchment quality grades according to its density. Remaining floaters are easily removed. Once clean, the highest parchment grade passes through an additional soaking phase of 8 to 12 hours.
Finally, the wet parchment is carried out to the drying field. During the first day of drying, the parchment rests on the pre-drying tables to let the excess water run off. Here, it is easier to detect and remove defects when the coffee is still wet. After one day, the drying field staff transfers the wet parchment to other tables where it will dry for up to 12 days. During this period, they regularly turn the parchment to ensure even drying and to avoid defects. Once dried, the coffees rest in a warehouse until the cooperative finds a buyer.
For more info about coffee in Ethiopia, visit our Ethiopia origin page.