Occurrence of ochratoxin A-producing fungi in raw Brazilian coffee

Ochratoxin A (OA)-producing fungi were identified in coffee at different st ages of maturation. The toxin was quantified in coffee during terrace dryin g and in coffee stored in barns. By direct plating, a high level of contami nation (100%) was found in the coffee beans studied, with the genus Aspergi llus representing 33.2%, of which Aspergillus ochraceus and Aspergillus nig er represented 10.3 and 22.9%, respectively, of the strains isolated from t he coffee beans. The capacity to produce ochratoxin was determined in 155 s trains of A. ochraceus and A. niger using both the agar plug method and ext raction with chloroform, giving positive results for 88.1% of the A. ochrac eus strains and 11.5% of the A. niger strains. Analysis for OA in the terra ce and bam coffee samples showed that, independent of cultivar, year harves ted, or production region, all except one of the samples analyzed showed my cotoxin levels below the limit suggested by the European Common Market (8 m ug/ ka), thus indicating that the problem is restricted and due to severe f aults in harvesting and storage practices.