Modernized processing installation for Arabica coffee.

Bugisu Co-Operative Union in Mbale, Uganda

The installation of the Bugisu Co-Operative Union for processing Arabica coffee that was recently modernized by Buhler represents a step into the future for Uganda's coffee industry. The installation improves and ensures the quality of this country's coffee, which is still the most important commodity exported. In mid-1993, the President of Uganda officially inaugurated the plant.

The Bugisu Co-Operative Union in Mbale decided in 1992 to modernize its obsolete coffee processing facility in order to raise coffee processing efficiency and output. Other major objectives of the project were to ensure consistently high quality of the coffee destined for export.

Operation of the updated plant is virtually dust-free, and monitoring and maintenance is easy. This is the first installation to be equipped with the new and improved SKP husker/polisher. Another first for a coffee processing installation of this type are the MWBG-V scale and the Catador MVSQ aspirator. A high degree of production readiness of the installation is ensured. The facility is equipped with two processing lines with a capacity of eight metric tons per hour, or 15,000 tons annually.

The customer specified that the Buhler equipment was to he installed in the existing building. Thanks to the good organization by the customer and the Buhler installation supervisor, production was interrupted for a short time only. During installation and start-up, the operating and maintenance crews underwent thorough training. Thanks to this extensive training, smooth production was achieved within a short time. The coffee delivered to the Bugisu Co-Operative Union, called parchment, undergoes a number of processing operations before being fit for export as green coffee.

Cleaning: The parchment is either discharged from storage bins or dumped directly into the receiving hopper. Upon weighing by MWBG-V scales, it is fed to MTRA cleaning machines and MTSB destoners.

Husking/polishing: The cleaned parchment is freed from its husks in the SKP husker/polisher. The firmly adhering silver skin is removed by polishing.

Calibration: Grading into various bean sizes is effected by Classifier MTRA sieving machines, which allow the standard to he achieved that is demanded by the Ugandan coffee authorities.

Classification: Catadors MVSQ free the green coffee from all types of sub-standard beans. This processing operation has the greatest influence on the quality of the brewed coffee in the consumer's cup, together with the subsequent colour grading change.

Colour grading: The separation of off colour beans is done by optico-electronic equipment. Sound beans have a colour ranging from green to bluish green. Sub-standard beans such as may result from fermentation errors exhibit a perceptible colour deviation to the point of the beans being black.

Bagging: The coffee destined for export is packed in 60-kg bags of jute or sisal with the aid for gross bagging scales. Spot checks ensure quality. The purchasers of the coffee are informed of the test results.

In-plant handling of the coffee is by mechanical and pneumatic conveyors. The installation is controlled from a central panel.

Uganda is one of Africa's biggest coffee exporters. Thanks to its high altitude and excellent climate and soils, the country can grow the Arabica variety in the Eastern regions bordering on Kenya and the Robusta variety in the other parts of the country.