Journal of Food Processing & Technology

Polyphenolic composition and antioxidant capacity of red wines made with the main grape varieties grown in Uruguay by two alternative methods of wine making

19^th International Conference on Food Processing & Technology

October 23-25, 2017 | Paris, France

Gustavo Gonzalez Neves, Maria Perez Serratosa, Guzman Favre and Diego Piccardo

University of the Republic, Uruguay
Universidad of Cordoba, Spain.

Posters & Accepted Abstracts: J Food Process Technol

Abstract:

The antioxidant capacity (AC) of wine is related to its polyphenolic composition. Genetic factors have a significant impact on the composition of grapes and wines. The wine-growing conditions modify the extraction of compounds from grape skins and seeds. The aim of this study was to evaluate the antioxidant capacity and the polyphenolic composition of the red wines of Merlot, Cabernet Franc, Cabernet Sauvignon, Syrah, Marselan and Tannat produced by two alternative methods of winemaking. The wines were elaborated by delayed extraction of anthocyanins plus extended maceration (DEA + EM) and by traditional maceration (TM). The wines were produced using 70 kg of grapes in each winemaking, with two replicates. The polyphenolic composition and AC were analyzed at 6 months after vinification. Phenolic families were quantified using classical spectrophotometric methods, while AC was evaluated using DPPH(2-propanol) and ABTS (1-butanol) methods. The AC values obtained with each method were significantly different. The wines of the different varieties showed significant differences in the polyphenolic composition. Tannat and Marselan wines had the highest antioxidant capacities and the highest polyphenol contents. Polyphenol indices were significantly correlated with AC measurements. Winemaking techniques showed a significant impact on the phenolic composition of the wines although this fact did not affect their AC. It can be concluded that the grape variety and the vinification conditions determined important differences in the polyphenolic composition and in the antioxidant capacity of the wines. The polyphenol contents of the wines of each variety presented great differences that can determine important variations in their sensory properties and chemical evolution.

Biography :

Gustavo Gonzalez Neves is a professor of enology in the department of food technology, faculty of agronomy in the University of Republic, Uruguay. He has completed his doctorate in Food Sciences from ENSAM, University of Montpellier, France in 2005. Before that he did his masters in viticulture and enology from Technical University of Madrid, Spain in 1992. In 1987 he completed his degree in agricultural engineering from faculty of agronomy, University of Republic, Uruguay.