Chemical Industry and Chemical Engineering Quarterly (Mar 2010)
Antioxidative activity of red wine with the in-creased share of phenolic compounds from solid parts of grape
Abstract
The structure and amount of phenolic compounds in the wine depend on the grapevine variety, agroecologic conditions and a way of vinification. The influence of pomace enrichment with solid parts of grape (stem and grape seeds) during maceration on the antioxidative activity of red wines was investigated. The antioxidative activity of red wines towards DPPH• and hydroxyl (•OH) radicals was determined by the electron spin resonance (ESR) spectroscopy. The addition of stem to the pomace had no significant influence on the antioxidative wine activity increase, whereas enriching of pomace with 120 g seeds/kg of pomace resulted in the increase of antioxidative capacity of a wine. In the wine enriched with tannins and flavan-3-ols from the seeds, the antioxidative activity towards DPPH• (AADPPH•) was 100%. None of the applied clarifiers showed a significant influence on the antioxidative activity of these wine samples. The antioxidative activity, measured as DPPH• scavenging activity, of the wine supplemented by seeds remained unchanged, showing 100% efficiency after the treatment by all tested fining agents. A significant difference in antioxidative activities towards hydroxyl radicals (AA•OH) between the two wines was found. The antioxidative activity of the wine Merlot was higher than the antioxidative activity of the wine Cabernet sauvignon.
