Impact of environmental conditions in vscs production during wine fermentation by Saccharomyces cerevisiae

Context and purpose of the study. The temperature increase related to ongoing climate changes is causing a progressive anticipation of the ripening time, negatively affecting grape quality at harvest.

Brazil is historically known at the international wine market as an importer, eventhough in the last decades there was an increase in quantity and quality of the internal production. Nowadays, about 40% of fine wines comsuption of the country are national ones. The main production region is called Serra Gaúcha, where the natural conditions are heterogeneous and viticulture is develloped in small properties, mainly done by the owners family.

Vitis vinifera L. and other Vitis have high genetic variations for cultivars or varieties. Many countries carried out strong efforts creating new clones of varieties, mainly focusing on plants free of viruses and other grapevine diseases, but also on different agronomical and enological characteristics of the plants. The aim of this study was to evaluate six clones of Merlot in the traditional viticulture of southeastern Brazil, focusing on distinct characteristics of yield, enological potential of grapes and wine typicality, in order to improve wine quality.

The rising trend of moderate wine consumption as a part of a healthy lifestyle promotes white wines with higher phenolic content because of their bioactive properties. Duration and temperature of the maceration process have a marked impact on the content and composition of wine phenolics. The aim of this study was to explore the effect of applying maceration processes of different durations and temperature on total phenolic content and flavan-3-ol compounds concentration of Malvazija istarska (Vitis vinifera L.) wines, an autochthonous Croatian white grape variety. Vinification took place at the Institute of Agriculture and Tourism (Poreč) where pre-fermentative two days cryomaceration treatment at 8 °C (CRYO), seven days maceration treatment at 16 °C (M7), and prolonged post-fermentative maceration treatments at 16 °C for 14 days (M14), 21 day (M21), and 42 days (M42) were studied and compared to non-maceration control treatment (C). Total phenolic content was determined by the Folin-Ciocalteu colorimetric method using a UV/VIS spectrophotometer and the results were expressed as gallic acid equivalents (mg/L GAE).

European regulations describe what elements must be given in the specifications of DPO determination ; mainly production conditions, links between quality and products characteristics and the physical traits of the production area. These elements are given in the “link to terroir” paragraph relating natural and human factors, detailed product characteristics linked to the geographical area and at last interactions between product originality and the geographical area.