Aspergillus section nigri in grapes cultivated in the tropical winery region of Brazil

Abstract

The main fungi responsible for the accumulat ion of ochratoxin A in grapes and wines belong to the genus Aspergillus Section Nigri. The production of this toxin by the fungus is related to abiotic factors and its presence may affect the quality and safety of the grapes grown and the wines produced. The aim of the present study was to assess the frequency of occurrence and the toxigenic potential of Aspergillus Section Nigri in grapes and seeds of Cabernet Sauvignon and Temp ranillo variet ies grown in the São Francisco Valley, northeast Brazil. To evaluate the distribution of these species and the toxigenic potential, samples of grapes of the Cabernet Sauvignon and Tempranillo varieties were co llected in three wineries. The percentage of contamination in the grapes of the two varieties analy zed was larger than that of the seeds, and statistically d ifferent between the wineries studied. A total of 94 filamentous fungi were identified and none Aspergillus carbonarius were identified. The relat ionship between the percentage of contamination in the wineries examined and the geographic location and climate is not very clear, since the wineries are located on the same lat itude and longitude, and are under influence of the same temperature (26°C).