Effect of cyprodinil+fludioxonil fungicides on fermentative process during winemaking

FALCONI P.; MERCADO L.; CIKLIC I.; GOMEZ M.; NAVARRO R.; MIANO J.L.; TORRES J.; COMBINA M.

Puerto Madryn, Argentina

Otro; 46th Annual Meeting of Argentine Society for Biochemistry and Molecular Biology Research; 2010

Different chemical compounds have been used to control fungus diseases in grapevines. Recently, new antifungal products have been introduced in the market to control these diseases. One of the most used products is composed by cyprodinil and fludioxonil (commercial name: Switch), which is characterized by a very short pre-harvest interval (PHI; 1 day). The winemaking process can be affected by fungicide residues present in grape musts. The aim of this study was to evaluate the effect of cyprodinil+fludioxonil fungicide on the alcoholic and malolactic fermentations during the winemaking process. The experiments conducted included combinations of different fungicide doses (0.05, 0.5, 1, 2, 5 mg L-1), yeast strains and malolactic bacteria. During fermentation, microorganism viability, fermentation performance and degradation of fungicides were analyzed. The fungicide concentration present in the must remained stable during fermentation and in the finished wines. Only the highest fungicide doses (5 mg L-1) reduced yeast viability and arrest the alcoholic fermentation. When compared at the maximum residue level, 1mg L-1 (MRL; SENASA Res. 507/08) for grape musts, no differences were found between yeasts on residual sugars and yeast viability. The malolactic fermentation and lactic bacteria viability were not affected at the MRL of 1 mg L-1.