Resíduos de fungicidas em vinhos de diferentes propriedades vitivinícolas do Rio Grande do Sul, Brasil, frente ao uso da tecnologia Thermal Pest Control a campo

Abstract

The use of chemical compounds in the wine industry is extremely high, thus, it is appropriate to identify and quantify pesticide residues in wine because grapes are one of the fruits with the highest number of pesticide applications in the country's agriculture. In order to reduce the use of pesticides, some winemakers have been using the Thermal Pest Control (TPC) technology in the management of their vineyards as an alternative to control pests. It is a technology that provides the high temperatures vines, providing a greater antimicrobial resistance. The objective of this study was to identify and quantify fungicides in white and red wines produced from grapes with and without the use of TPC technology for their cultivation in different wine properties of Rio Grande do Sul. Samples of Tannat, Chardonnay and Cabernet Sauvignon varieties from the 2011/2012, 2012/2013 and 2013/2014 harvests were collected in three wine properties of RS. Vinification process was performed in laboratory scale separately for grapes using no TPC technology (control) and grapes using TPC (TPC). The modified QuEChERS acetate method was used for sample preparation. Afterwards, analyzes were carried out using UHPLC-MS/MS for determination of fungicides. Boscalid, procymidone, pyraclostrobin, pyrimethanil, thiophanate-methyl and tetraconazole were detected above the LOQ in both treatments. In control and with TPC, pyrimethanil presented higher frequency (85.71%) and averages (26.33 and 30.16 μg L-1), respectively. There was no significant difference between the white and red wines. In Chardonnay wines, 2012/2013 harvests, the fungicide pyrimethanil was statistically different, with an average of 64.67 μg L-1 (control), and 111.12 μg L-1 (TPC), thus, higher levels for wines with the use of TPC technology were observed. In Chardonnay wines, 2013/2014 harvests, showed the higher average of procymidone in control (6.47 μg L-1) than in treatment with TPC (0.46 μg L-1). In Cabernet Sauvignon wines, 2013/2014 harvests, presented a higher average of procymidone in treatment with TPC (129.73 μg L-1) than in control (3.69 μg L-1). Therefore, the presence of fungicide residues was observed in this study, but none of the compounds presented levels above the MRL established for grapes considering their mass corrections. These results show higher concentrations of residues for those wines produced from grapes submitted to TPC technology. We found no references in literature about fungicide residues in wine whose grapes were submitted to this technology, which leads us to believe this is the first study on the subject.