Abscisic acid applications increases color in grapes and juice of 'Isabel'

Juices produced by American grapes add a great value to producers and has great advantages over the wine, since alcohol free and having the same nutraceutical properties, the juice can be consumed at any time by anyone. The cultivar 'Isabel' is the foremost among the cultivars used for the preparation of grape juice, however, has poor color and the yield improvement process of the grapes in order to produce juice. The objective of the study was to evaluate the effects of applying abscisic acid (ABA) on the phenolic composition of berries and juice of cultivar 'Isabel'. The experiment was conducted in the state of Rio Grande do Sul, in the municipality of Pinto Bandeira, with 'Isabel' cultivar of Vitis labrusca. The experimental design was randomized blocks with five replications. Applied in the veraison stage in five levels of abscisic acid (0, 200, 400 600 and 800 ppm). After harvesting, the assessment of physical, chemical and phenolic compounds present in the skin characteristics and whole juice were performed. The application of abscisic acid provided increased levels of polyphenols, anthocyanins and the color intensity in the 'Isabel' grape and juice produced, increasing linearly to 70% anthocyanins, 119% polyphenols, 61% of the intensity of the color of the juice produced from 'Isabel' grapes.