Disappearance of fenhexamid residues during wine-making process.

The main objective of this work was the study the influence of different wine-making techniques on the pesticide residue elimination from grapes to wine. In order to that, the maceration time effect (6 and 15 days) was studied on the final fenhexamid residue content in wine. And also, the influence of a prefermentative maceration at low temperatures (5 and 15 degrees C during three days of the maceration period) on the residue disappearance was determined in both maceration times. Determination of the residues of fenhexamid was made by GC-ECD, following extraction by an on-line micro method, with a mixture of acetone/dichloromethane (50/50 V/V) as extractant. The maceration time does not produce significant differences in the final pesticide content in wine. However, if the prefermentative temperature increases, there is a high elimination of the fungicide residues. The highest fungicide elimination was obtained in wines with long maceration and a prefermentation at 5 degrees C.