Abstract
Operating conditions affect Ochratoxin A (OTA) extraction in roasted coffee. It is thus that the OTA content found in the beverage is greater than that found in the roasted coffee used to prepare it. Three extraction parameters were studied for roasted coffee : type of extraction solvent (alkaline, neutral, acid), temperature (ambient temperature/23°C, 60°C and 85°C) and extraction time (5, 20, 30, 40, 50, 60 and 80 min). The alkaline solvent that is used in the method recommended by the European Union, extracted OTA better, but a maximum content was obtained at 60°C after 50 min. At least a 100% improvement in extraction was obtained when compared to the EU usual quantification method that is carried out at ambient temperature. It turned out that the OTA extraction parameters for roasted coffee, as defined by that method, were not optimum and needed to be modified. These results were verified in double extraction experiments showing that OTA is not completely extracted by this method. Confirmation was obtained by comparison of extraction methods on several commercial samples of roasted coffee.