In Kenya, after a certain lot has been processed, it will be delivered to the Marketing Agent (MA) in parchment by the producer or cooperative. The MA then, will mill and grade the lot by shape and size, and give this lot an unique "Outturn Number" (ON), before delivering a sample to the Nairobi Coffee Exchange. This ON will be crucial to provide transparency and traceability to the system.
The lot now has a unique ON, but many different grades that can range from:
E (Screen 20)
AA (Screen 18/19),
AB (Screen 16/17),
C (screen 14-15),
HE, MH, ML, T, TT, UG1, UG2 (Undergrades)
The system assumes that the bigger the bean, the better the cup. However, that is not always correct.
Considering the great number of samples and the limited time we have, we focus only in the AA, AB, and PB grades. Through that focused research, the centralized system of the Nairobi Coffee Exchange allows us, to discover some hidden jewels from very remote areas of the country, that it would have been impossible to find just travelling around.
In simple words the Nairobi Coffee Exchange works as a weekly Cup of Excellence, stimulating competition and prices for the best lots.