Abstract:
Coffee is the most important agricultural export commodity to fetch foreign currency. It needs
to fulfill the quality standards of safety up to maximum tolerable level in order to get
acceptance from international coffee markets. However, coffee is naturally associated with
several mycoflora and some of them may produce Ochratoxin A unless careful handling
measures are in place. Therefore, this research was initiated with the objectives of identifying
mycotoxigenic fungi associated with coffee todetect and to quantify Ochratoxin A from coffee
beans collected from the soil, wet and dry processing coffee mills. A total of 77 coffee samples
were collected from Mana, Goma, Gera and Limu Kosa districts of Jimma zone, Oromia
Regional State of Ethiopia. Malt Extract Agar (MEA) was used for isolation and identification
of fungi associated with coffee using macro and microscopic characteristics. HPLC was used
to detect and quantify Ochratoxin A from green coffee bean. Different fungal genera,
including: Aspergillus, Fusarium, Penicilium and Rhizopus were found associated with coffee
beans from different coffee processing methods having different altitudes. Accordingly,
Aspergillus spp (84.74 %), Fusarium spp (8.75%), Penicillium spp (5.49%) and Rhizopus spp
(1.02%) were recorded. The mean ochratoxin A (OTA) detected from different coffee samples
were; 6.24µg/kg, 2.05µg/kg and 1.2µg/kg from soil, dry and wet processed samples,
respectively. Mean ochratoxin A concentration level was the highest in coffee collected from
soil (6.24µg/kg) while the quantity was relatively the least from wet processed coffee samples.
Likewise, the highest fungal incidence was encountered in coffee beans collected from soil
and the lowest fungal incidence was observed in wet processed coffee beans. The present
study revealed that the degree of importance of mycotoxigenic fungi in Jimma zone. To
manage the mycotoxigenic fungi and their mycotoxins, avoiding collecting coffee from soil,
controlling insect pest infestations, avoiding mold formations, controlling moisture content of
coffee are recommended to get high quality and market competitive coffee beans.
