Incidence of microflora and of ochratoxin A in green coffee beans (Coffea arabica).
Coffee is produced in tropical countries around the Equator where climatic conditions are favourable for fungal development and mycotoxin production; however, mycotoxins do not only occur in the tropical countries. The aim was to evaluate the mycoflora and possible incidence of ochratoxin A (OTA) in 60 samples of green coffee beans from Brazil. The mycological evaluation was carried out using a conventional method and the OTA was determined using sequential phenyl silane and immunoaffinity column cleanup followed by HPLC. The detection limit was 0.2 microg kg(-1). Practically all samples (91.7%) were contaminated with moulds. The dominant fungal genus was Aspergillus, including A. niger (83.3%), A. ochraceus (53.3%) and A. flavus (25.0%). The occurrence and the levels of the genus Cladosporium (16.6%) and Penicillium (10.0%) were substantially lower than Aspergilli. Twenty samples (33.3%) of 60 were contaminated with the toxin at levels ranging from 0.2 to 7.3microg kg(-1). The average concentration was 2.38 microg kg(-1). All positive samples showed OTA levels below the limit suggested by the European Union (8 microg kg(-1)).
Martins
M L
ML
Departimento de Higiene Pública, Serviço de Micologia, Lisbon, Portugal. marina.martins@lniv.min-agricultura.pt
Martins
H M
HM
Gimeno
A
A
D001938:Brazil; D002273:Carcinogens / Q000032:analysis; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D003069:Coffee / Q000737:chemistry* / Q000382:microbiology*; D005506:Food Contamination / Q000032:analysis*; D005516:Food Microbiology; D005658:Fungi / Q000145:classification / Q000302:isolation & purification* / Q000378:metabolism; D006801:Humans; D009793:Ochratoxins / Q000032:analysis*
D002273:Carcinogens; D003069:Coffee; D009793:Ochratoxins; C025589:ochratoxin A