Macrowine 2021
IVES 9 IVES Conference Series 9 Prevention of wine oxidation during barrel aging: an innovative method to measure antioxidant

Prevention of wine oxidation during barrel aging: an innovative method to measure antioxidant

Abstract

Wine oxidation is a problem that affects the freshness, the aromatic profile, the colour and also the mouthfeel of the wine. It mainly concerns white wines. Oxygen interactions with wine compounds lead to the phenomena cited above that are responsible for the depreciation of these wines. Barrel aging is a crucial step in the wine process because it allows many modifications as wine enrichment, colour stabilization, clarification and also a slow oxygenation of the wine. Effects of the oak barrel have to be known to prevent oxidation of the wine. We have been interested in the main antioxidant compounds released by oak barrels to the wine and we have developed an innovative method to reach directly these antioxidant compounds at the oak stave surface. The method is based on an innovative sensor that can be applied directly on the oak and measure several part of the stave at the same time. The apparatus needed for this sensor management is a classical electrochemical system, namely a potentiostat instrument, reference and counter electrodes. The working electrode used is this innovative sensor made from twelve gold ultramicroelectrodes. Direct application of the sensor on the oak stave leads to the recording of a current. This is due to the release of electrons from oak compounds. Those are oxidized due to the electrochemical method but they are the same that will provide protection to the wine in being oxidized instead of wine compounds. The current recorded per oak surface leads to an index that we called antioxidant capacity (CAOX). It represents the ability of the oak barrel to protect wine from oxidation. The higher it is, the better the wine is protected. This sensor has been used to characterize oak wood according to several parameters: length of seasoning, type of grain, toasting intensity and so on. Taking into account all these results, we managed to make a barrel that optimizes all parameters and provides the better protection against oxidation without giving strong woody styles. We tested the first prototypes on white wines of several wineries from Burgundy. The CAOX of the wines aged in prototype was always higher than the same wine aged in a reference barrel after a few months of barrel ageing. Moreover those wines were more appreciated because of their freshness, respect of the fruit, aromatic purity and tautness.

Publication date: May 17, 2024

Issue: Macrowine 2016

Type: Poster

Authors

Marie Mirabel*, Vincent Renouf

*Chêne & Cie

Contact the author

Tags

IVES Conference Series | Macrowine | Macrowine 2016

Citation

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