Oak wood barrel tannin potential builds white wines oxidative stability and contributes to wine metabolomics fingerprint

Resveratrol is a well-known wine constituent with a wide range of activities. In wines, resveratrol can be oxidized to form various derivatives including oligomers [1]. In this study, resveratrol derivative transformation in hydroalcoholic solution was investigated by oxidative coupling using metals. De novo resveratrol derivatives were synthetized and analysed by NMR and MS experiments

Oenological tannins are products extracted from various botanical sources, such as mimosa,
acacia, oak gall, quebracho, chestnut and tara. The polyphenolic component is obtained through a solid-liquid extraction also using specific solvents, then removed by evaporation or freeze-drying. Tannins are employed in two phases of winemaking, during the pre-fermentative phase or during fining with different purposes such as modulate antioxidant activity, colour stabilization, bacteriostatic activity, protein stabilization and modulation of sensory properties. To date, the current regulatory framework is not very clear. In fact, the Codex Alimentarius classifies commercial tannins as “food additives” but also as
“processing aids”. The main distinction is that “additives” have a technological function in the final food, whereas “processing aids” do not. In this sense, oenological tannins, despite the technological treatments, could contain aromatic compounds of the botanical species they belong to and release them to the wine.

Copper and iron are known to substantially impact wine stability through oxidative, reductive or colloidal phenomena. However, the binding of metal ions to different wine components under wine conditions, and the impact of this binding on the ability of the metal ions to induce spoilage processes, is not well understood. This study surveyed a range of red and white wines for an understanding of the variability of broad metal categories within the wines. The techniques utilized included an electrochemical constant current stripping potentiometry technique (ccSP), and solid phase extraction (SPE) fractionation of wine with subsequent analysis of the metal content of each fraction by inductively coupled plasma – optical emission spectroscopy (ICP-OES).

Grapevine phenology is advancing with increased temperatures associated with climate change. This may result in higher fruit sugar concentrations at harvest and/or earlier compressed harvests and changes in the synchrony of sugar with other fruit metabolites. One adaptation strategy that growers may use to maintain typicity of wine style is to change cultivars. This approach may enable fruit

The Columbia Valley American Viticultural Area (AVA) of the Pacific Northwest, USA is the world’s largest officially recognized viticultural area with basalt bedrock.