Selective harvest for the ‘Petit Verdot’ vinification from “Campanha Gaucha” in Rio Grande do Sul (RS), Brazil

The State of Rio Grande do Sul (RS) is the main producer state of fine grapes (Vitis vinifera L.) for the preparation of fine wine. Located in the southern half of the RS, the Campanha Gaucho is a region bounded by temperate grasslands called the “Pampa” Biome. Its climatic characteristics has enabled it to become one of the most promising regions for producing fine grapes for winemaking. In this scenario, after a selection of clusters with different levels of maturity, we sought to identify the winemaking characteristics of 'Petit Verdot', from the elaboration of a varietal wine in the traditional method, as well as their sensory characteristics (smell/taste) as a final analysis. Manual sorting of the grape bunches was defined into three divisions with three repetitions each (12 kg of grapes replication-1, totaling 108 kg), these were: sorting T1: mature grapes; sorting T2: incomplete mature grapes and; sorting T3: without sorting the bunches. Grape juice was analyzed by Fourier transform infrared spectrometry (FTIR); where we evaluated the total soluble solids, pH, total acidity, reducing sugar, malic and tartaric acid. In wine, alcohol, pH, total acidity, volatile acidity, reducing sugars, glycerol, malic and lactic acid were evaluated. Sensory analysis of wine for evaluation of its organoleptic characteristics was also carried out. The data was submitted for analysis of variance and mean comparison Tukey test at 5% significance. There were no significant variations of the compounds analyzed in the grape juice and wine cultivar 'Petit Verdot'. Of the sensory analysis results, only the acidity resulted differently between sorting T2 and sorting T1 treatments that presented higher acidity. In this context, the selection of clusters of different levels of wine for aging was not necessary for improving the quality of the wines produced.