Incidence of microflora and of ochratoxin A in green coffee beans (Coffea arabica)

Food Addit Contam. 2003 Dec;20(12):1127-31. doi: 10.1080/02652030310001620405.

Abstract

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)).

MeSH terms

  • Brazil
  • Carcinogens / analysis
  • Chromatography, High Pressure Liquid / methods
  • Coffee / chemistry*
  • Coffee / microbiology*
  • Food Contamination / analysis*
  • Food Microbiology
  • Fungi / classification
  • Fungi / isolation & purification*
  • Fungi / metabolism
  • Humans
  • Ochratoxins / analysis*

Substances

  • Carcinogens
  • Coffee
  • Ochratoxins
  • ochratoxin A