Coffee bean supplier, Miko Coffee, has installed an optical sorting machine to reduce the amount of foreign material in its beans.
The company, based in Antwerp, Belgium, has reported a 95 per cent fall in customer complaints once the optical sorter was set up to remove small sticks and other foreign material from its coffee.
Before installing the system, sticks or small pieces of stone in its coffee beans were causing customers’ grinders to jam.
Miko Coffee invested in a Sortex A system from Bühler. The Sortex A range of optical sorters use advanced inspection technology that identifies differences based on structural properties, enabling the sorter to reject unwanted material of the same shape and colour as the coffee bean.
Previously, Miko Coffee had used a machine to sieve coffee beans before roasting, but its small mesh meant good coffee beans were being sorted out, which affected yield. Using a larger mesh would boost yield, but only remove large foreign matter.
To compound the problem, wood has almost the same specific weight as green coffee and can therefore not be removed by a destoner.
Miko Coffee now uses a large-mesh sieve machine to remove larger foreign matter, before passing them through the Sortex A machine. This leads to much less waste, but with far more foreign material removed, including small pieces of wood.
Each day, Miko Coffee takes delivery of one or two truckloads of green coffee, amounting to 8,000 tons a year. About 50 tons of green coffee is sorted each day, with the Sortex A running for 10 hours. Every bean is sorted before it is blended and roasted, which ensures higher quality, cleaner coffee, free from defects and foreign material.