Influence of the storage condition on physicochemical characteristics of red wines from São Francisco Valley, Brazil

Abstract

In the São Francisco Valley, Northeast of Brazil, tropical wines have been produced thirty years ago. Vines can produce twice a year and wine stability can change according to the harvest date. Normally wines elaborated from grapes harvested between November-December have a fast evolution, while wines from grapes harvested between June-July can have greater stability. Annual average temperature is 26°C, but in the summer (November) the maximum average is 31°C. After bottling, another factor influencing wine stability is the storage condition. In this way, the aim of this study was to evaluate the influence of the conditions of bottle storage on physicochemical characteristics of commercial Syrah tropical wines, from grapes harvested in November 2014. Wine bottles were stored in two conditions, in the cellar at 18 ± 2 °C, and in the shelf, in ambient temperature. Wines were analyzed one, four, seven and ten months after bottling, by HPLC, to determine classical analyses, phenolic compounds and antioxidant capacity. As results, anthocyanins, flovonols, flavanols and stilbene reduced their concentrations in both conditions along ten months, while galic and p-coumaric phenolic acids increased concentrations after ten months in both conditions. But wines stored in the cellar presented higher values of malvidin-3-glucoside as compared to wines stored in shelves. Wines presented 120 mg L-1 of malvidin-3-glucoside one month after bottling, and ten months after storage presented significant differences (59.2 mg L-1 in wines from cellar and 17.5 mg L-1 in wines from shelves). We conclude that storage conditions can influence tropical wine stability and may increase shelf life if temperature is controlled and stable along time.