67B-29 |
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P. C. F. DA SILVA and P. C. Stringheta. Dep. Tecnologia de Alimentos, Universidade Federal de Viçosa, Av PH Rolfs Campus Universitário Viçosa - MG, Viçosa, 36571-000, Brazil According to certain studies, wines constitute an excellent source of dietary polyphenolic compounds, which appear to exhibit multiples biological effects. But still there is a considerable lack of information regarding the influence of grape composition on the antioxidant capacity of their byproducts. The present study represents an approach with respect to determining the polyphenolic content of the Cabernet Sauvignon grape fractions and of its respective elaborated wine, as well as evaluates the in vitro antioxidant potential. Analyses of total antioxidant activity (TA), DPPH radical scavenging activity (SA), total polyphenol (TP) and tannin (T) content of the grape fractions and wine were performed. The highest TP concentrations were found in the wine and seed extract (p<0.01) which were approximately 2 times higher than the skin extract and 12 times higher than the pulp extract. The highest T concentration was found for the seed extract (p<0.01), which was 4 times higher than the skin extract, 23 times higher than the wine, and 84 times higher than the pulp extract. The skin and seed extracts showed little TA only in low TP concentrations, however all the extracts and wine obtained similar higher results in higher TP concentrations. Even in the lowest TP concentration, the wine showed a good performance. In the lowest TP concentration, the seed extract exhibited (p<0.01) the best SA (90,7 %), skin (88.5 %), wine (80.5 %), and pulp (76.5 %). This study shows that the seeds and the grape skins play an important role in the overall antioxidant status of red wines. Therefore, an adequate change in red wine making process in order to obtain a new produce with health allegations is feasible. Furthermore, evidences in this work suggest that white grapes deserve a greater attention in this way, since they also contribute as dietary antioxidants through their wines.
Session 67B, Food Chemistry: Antioxidants and bioactive agents
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