Optimization of phenolic compounds in grape extract malvasia variety

Abstract

The pomace presents high levels of phenolic compounds with interesting antioxidant properties for use in food and / or in different biological systems in its composition. The conditions for the extraction of phenolic compounds were optimized using the response surface method (MSR) in grape marc Malvasia variety, in Zulia state, Venezuela. The content of total phenolic compounds was quantified by the Folin Ciocalteu Method and the antioxidant activity of the extracts by the ABTS method. The effects of the concentration of the solvent and the temperature of extraction in the evaluation of the content of phenolic compounds were studied. The most suitable conditions resulting from the MSR for the grape marc coming from the Malvasia variety was 92.5% Ethanol and 65 °C. The chemical analysis of the optimized extract reported an antioxidant activity of 21.08 ± 2.69 mmol TEAC.100g-1. Key words: Vitis Vinifera, phenolic compounds, extraction, optimization, antioxidant.