Evolução da maturação, análise físico-química e sensorial de uvas e sucos de videiras Vitis labrusca e híbridas

Abstract

Brazilian viticulture is in constant expansion and the main destinations of the production are the processing, the elaboration of wines, juices and derivatives and the consumption in natura. Thus, the aim of this work was to evaluate the maturation evolution, the physical-chemical characteristics and the sensorial acceptance of grapes in natura and juices in the southern region of Rio Grande do Sul. The study was divided in three experiments. In the first study, the maturation index and the physical and productive characteristics of ‘Niágara Rosada’ and ‘Niágara Branca’ vines were evaluated. The experimental design was in randomized blocks, with five replications and five plants per plot. The variables analyzed during maturation were soluble solids (SS), pH, titratable acidity (TA) and SS/TA ratio, from the beginning of maturation to harvest. At the time of harvest, the mass and the length of the bunches, the mass and the diameter of the berries were evaluated. The average number of bunches per plant was also recorded and the yield per plant (kg.plant-1) and yield (t.ha-1) were estimated. In the second experiment, the physical-chemical characteristics and the sensorial acceptance of ‘Niágara Rosada’ and ‘Niágara Branca’ grapes produced in the city of Pelotas-RS were evaluated. The experimental design was a randomized complete block design with two levels, five replications and five plants per plot. The evaluated variables were: bunch length, berry diameter, soluble solids content, pH and titratable acidity. Fifty judges evaluated the color, aroma, sweetness, acidity, taste and overall acceptance attributes using a hedonic scale of nine points, in addition to the intention to buy. In the third experiment the chemical characteristics and the sensorial acceptance of juices and cuts of ‘Bordô’ and ‘Niágara Rosada’ grapes were analyzed. The experimental design was in a one-factor scheme, with five levels. The treatments consisted of juices elaborated with: ‘Bordô’ (100%); ‘Bordô’ (70%) + ‘Niágara Rosada’ (30%); ‘Bordô’ (50%) + ‘Niágara Rosada’ (50%); ‘Bordô’ (30%) + ‘Niágara Rosada’ (70%) and ‘Niágara Rosada’ (100%). The chemical characteristics evaluated were: soluble solids, pH and titratable acidity; and the sensory were color, aroma, taste, body and overall acceptance of the samples, using a hedonic scale of nine points. In the first experiment, it was verified that both cultivars presented maturation, satisfactory physical and productive characteristics in the region under study. In the second experiment, it was verified that the ‘Niágara Rosada’ and the ‘Niágara Branca’ were well accepted by the evaluators. In addition, in the third study it was possible to observe that juices made with 100% ‘Bordô’ grape and ‘Bordô’ juice cut with up to 50% ‘Niágara Rosada’ are good alternatives for juice production.