Aspergillus carbonarius in syrah grapes grown in three wine-growing regions of Brazil

Abstract

Contamination by ochratoxin A (OTA) in agricultural products grown in regions with different climate conditions is difficult to predict since this contamination depends on a complex interaction of factors. Thus, the aim of this study was to use a mathematical model to predict OTA synthesis by Aspergillus carbonarius in grape (Vitis vinifera) of the Syrah variety grown in three wine-growing regions, considering the mean monthly temperature of the environment and water activity and pH of grape. Results indicate that the greatest risks of contamination by the toxin are in the months when the temperature is below 19.0°C and these months are just before grape harvest. However, with the predicted increase in temperature, these conditions change, i.e., they are no longer favorable to OTA synthesis, thus reducing the risks of the presence of the toxin in cultivated grapes. For the tropical region, the current environmental temperature and water availability to grape are not favorable to OTA synthesis, showing that even if A. carbonarius is present in the crop, it does not encounter suitable conditions of environmental temperature, water activity, and grape pH to synthesize OTA