Análise físico-química e atividade antioxidante de suco de uva das variedades Isabel, Niágara Rosada e Niágara Branca produzidos através de panela extratora

Abstract

The western region of Paraná has characteristics conducive to viticulture, as the Isabel Precoce, Niágara Branca and Niágara Rosada grape varieties are adaptable under these conditions, allowing their evaluation for the production of grape juice. Production by extractor pan with steam drag is the cheapest and most efficient way. The present work seeks to evaluate the physical-chemical properties and its capacity of antioxidant activity, of the grape juice produced with these cultivars, by extractor pan, as well as the evaluation of a sample of commercial juice. The physical-chemical analysis methods are pH, total titratable acidity, soluble solids, density and assessment of antioxidant activity by DPPH and ABTS methods. The results obtained through the physical-chemical analyzes for the 2022 and 2023 Isabel harvests showed, respectively, average values of pH 3.40 and 3.51, soluble solids (SS) 16.33 and 19.58 °Brix, density 1.062 and 1.075 g cm-3 and mean total titratable acidity (TTA) of 65.83 and 69.91 meqL-1. The Niagara Branca and Rosada grapes showed, respectively, pH values 3.71 and 3.65, density 1.08 and 1.07 g cm-3, SS 19.42 and 18.08 °Brix and TTA values of 26,33 and 37.50 meq L-1. For the commercial juice, the values obtained were: pH 3.26 density 1.06 g cm-3, SS 16.57 °Brix and TTA acidity was 60.50 meq L-1. ABTS values were 4.190 and 6.862 mmol L-1 for Isabel 2022 and 2023, 3.283 and 7.67 mmol L-1 for Niagara Branca and Rosada grapes, and the commercial 5.738 mmol L-1. The DPPH method showed values of 3,390 and 3,481 mmol L-1 for Isabel's 2022 and 2023 grape harvest, for Niagara Branca and Rosada 2,809 and 4,222 mmol L-1 and for the commercial 3,707 mmol L-1. All values were compared with the literature and with the minimum or maximum limits reached by Brazilian legislation. A great correspondence between the results can be verified.