Antioxidant activity, anthocyanins and organic acids content of grape juices produced in Southwest of Minas Gerais, Brazil

Abstract

Phenolic compounds and anthocyanins content in grape juices varies in the cultivar, ripening and climate characteristics. The objective of this work was to characterize and evaluate antioxidant activity of grape juices produced in southwestern Minas Gerais. Grapes were harvested, sanitized and the juices from cultivars 'Bordô', 'Isabel Precoce', 'BRS Violeta' and 'BRS Rúbea' were produced in artisanal equipment by steam extraction and stored for 120 days. The following analyzes were performed during storage: color (L *), pH, soluble solids, titratable acidity, anthocyanins, antioxidant activity (DPPH and β-caroteno/linoleic acid), total phenolics, vitamin C and organic acids. Among the cultivars evaluated, the consumption of grape juice from cultivar 'BRS Violeta' is suggested due to its higher content of vitamin C, antioxidant activity, total phenolics, anthocyanins, and also due to a better physicochemical characteristic showed, when compared to the juices of the other cultivars.Index terms: Vitis labrusca, phenolics, vitamin C, organic acids. RESUMOO teor de compostos fenólicos e antocianinas em sucos de uva varia de acordo com a cultivar, maturidade e características climáticas. Neste trabalho, objetivou-se a caracterização e a avaliação da atividade antioxidante de sucos de uvas americanas produzidas no sudoeste de Minas Gerais. As uvas foram colhidas, sanitizadas, sendo as grainhas e demais partes dos cachos descartadas. Então, os sucos das cultivares Bordô (Vitis labrusca), Isabel Precoce (Vitis labrusca), BRS Violeta (híbrida) e BRS Rúbea (híbrida) foram produzidos em equipamento artesanal por extração em vapor de água, acondicionados em frascos de vidro e armazenados a 18ºC±2ºC por 120 dias. As seguintes análises foram realizadas ao longo do armazenamento: cor (L*), pH, sólidos solúveis totais, acidez titulável, , antocianinas, atividade antioxidante (DPPH e β-caroteno/ácido linoléico), fenólicos totais, vitamina C e ácidos orgânicos. Entre as cultivares avaliadas, sugere-se o consumo do suco de uva da cultivar BRS Violeta, pelos maiores valores de vitamina C, atividade antioxidante, fenólicos totais, antocianinas, além de apresentar melhores características físico-químicas quando comparada ao suco das demais cultivares. Termos para indexação:Vitis labrusca, fenólicos, vitamina C, ácidos orgânicos.

Optimization of the Mixing of Hibiscus Flower (Hibiscus rose sinensis) Extract as a Lip Balm Color with Variations in Concentration

“…Apart from their bright and attractive colors, their solubility was also quite high in water. 12,13 The texture of F1 looked drier than that of F2, F3, and F4 because F1 did not have an antioxidant that functioned as a moisturizer. In addition, there was no aroma caused by F1 because there was no active ingredient in Hibiscus flower extract, while F2, F3, and F4 had a distinctively strong Hibiscus flower aroma.…”

Wine Grapes Ripening: A Review on Climate Effect and Analytical Approach to Increase Wine Quality

“…A study found that moderate exposition to radiation and temperature increases the accumulation of anthocyanins [53]. Many studies have shown the impact of different climates in anthocyanins accumulation [1,47,54] and organic acids accumulation [55][56][57]. In a study performed in Alentejo, it was found that despite total anthocyanin content have increased during maturation in both years a much warmer and dryer year (with less pluviosity) had a positive impact on the synthesis and accumulation of anthocyanins [1].…”

Bioactive Properties of Different Parts of Vitis labrusca L. Fruit

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