OCHRATOXIN A AND AFLATOXINS QUANTIFICATION IN GREEN COFFEE BEANS: MYCOLOGICAL AND ANALYTICAL STUDY

Abstract

This study investigated the contamination of 22 selected green coffee bean samples grown in South and Central America by microscopic filamentous fungi and their potential for mycotoxin (ochratoxin A, aflatoxins) production. A total of 2860 isolates belonging to 11 genera, including Aspergillus, Penicillium, Fusarium, Syncephalastrum, and Rhizopus, were identified. The genus Aspergillus was present in all samples (frequency of occurrence – Fr 100.00%, relative density – RD 88.49%) and exhibited the highest frequency, with sections Nigri (Fr 95.45%, RD 49.86%), Aspergillus (Fr 90.90%, RD 8.36%), and Flavi (Fr 77.27%, RD 27.94%). Toxigenic screening by thin layer chromatography (TLC) revealed that 27.8% of Aspergillus and 71.4% of Penicillium tested isolates were capable of producing mycotoxins, including ochratoxin A and aflatoxins. While aflatoxins were not detected in the green coffee beans by HPLC-FLD, ochratoxin A was found in 68.2% of them at low concentrations (from 0.375 to 1.487 ng/kg). These findings emphasize the importance of monitoring fungal contamination and mycotoxin levels in green coffee beans to ensure food safety and quality in the coffee industry.