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L’ochratoxine A (OTA) est une toxine cancerogene produite par certaines moisissures. Elle contamine de nombreux aliments et notamment le cafe dans lequel elle est retrouvee a toutes les etapes du parcours technologique du champ a la tasse. Cette etude a pour objet de faire le point sur les etapes critiques des procedes de transformation du cafe, que ce soit durant les traitements post-recolte ou pendant la transformation en produit consommable, en ce qui concerne sa contamination par l’OTA. La qualite et le type de traitements post-recolte ont une influence non negligeable sur le niveau de contamination en OTA des grains verts. Les defauts agronomiques (insectes et attaques fongiques) contribuent egalement a un niveau eleve d’OTA dans le cafe vert. Diverses etudes effectuees sur l’impact de la torrefaction mettent en evidence une degradation thermique de l’OTA. Toutefois, la contamination initiale des feves, le procede utilise et le degre de torrefaction influencent fortement cette degradation thermique et donc la concentration residuelle en OTA dans les grains torrefies. Finalement, il apparait que c’est la maitrise de la contamination en amont par de bonnes pratiques agricoles et par les traitements post-recolte qui est le plus sur gage de salubrite pour la boisson.

The recent public health issues affecting food chains have prompted health authorities to increase their vigilance concerning the presence of contaminants in staple foods. This change in position has led to the introduction of regulations (Regulations (EC) No. 1881/2006 and 149/2008 of the European Commission). Coffee, being one of the most widely consumed beverages in the world, is no exception and is now subjected to these provisions. The known origins of coffee contamination are: on one hand, pesticides used during culture and storage and, on the other hand, mycotoxines and polycyclic aromatic hydrocarbons (PAH) that arise from processes of drying and roasting.Pesticides are used in modern agriculture to reduce the impact of pests and diseases in crops. Nevertheless, pesticide residues in green coffee remain relatively limited during agricultural treatments. The maximum risk of contamination occurs during transportation and storage. Mycotoxins are toxic chemicals produced by certain fungi that grow on foodstuffs. Ochratoxin A (OTA) is the main mycotoxin found in coffee. It is a secondary metabolite produced by several toxigenic species of Aspergillus and Penicillium. It has been shown to have nephrotoxic, carcinogenic, teratogenic and immunosuppressive effects. The presence of OTA in coffee beans may be linked to environmental conditions and to post-harvest processing conditions. The polycyclic aromatic hydrocarbons found in coffee may be exogenous (contamination during drying) or endogenous (formation during roasting). PAHs are toxic and/or carcinogenic compounds. For each family of contaminants, the current knowledge, regulations and effective ways of limiting their contents are discussed.