An Approach to the Study of the Interactions between Ellagitannins and Oxygen during Oak Wood Aging

Abstract

During the aging of red wine in oak wood barrels, or in alternative aging systems, interactions between the compounds released from wood, the compounds of the wine, and oxygen can take place. The main objective of the present work was to study oxygen-ellagitannin interactions by monitoring their levels in three model systems, all containing the same amounts of French oak chips and differing only in the oxygen content: total absence, only the oxygen released from the chips, and air-saturated (model systems F, OW, and OS, respectively). This study has highlighted the influence of oxygen in the ellagitannins' evolution and the relevance of the oxygen trapped into the oak chips, reporting for the first time the kinetics of oxygen release to the model wine. Furthermore, the indirect contribution of oxygen to the ellagitannins' disappearance by boosting autoxidative reactions has also been pointed out. Vescalagin seems to be the ellagitannin most affected by the initial oxygen levels.

Alternative Woods in Enology: Characterization of Tannin and Low Molecular Weight Phenol Compounds with Respect to Traditional Oak Woods. A Review

“…Wood composition depends not only on species but also many other factors such as silvicultural, geographic origin and cooperage processing, which affect the extractable fraction [5,13,23,35]. Ellagitannins are transferred to the wine during aging, contributing to sensations of bitterness and astringency [36][37][38] and behaving as antioxidants due to their capacity to consume oxygen [39,40]. Moreover, ellagitannins directly affect wine color via reactions with anthocyanins forming red orange anthocyanin-ellagitannin complexes but are much more stable over time than free anthocyanins [41][42][43].…”

Oxygen Consumption by Red Wines under Different Micro-Oxygenation Strategies and Q. Pyrenaica Chips. Effects on Color and Phenolic Characteristics

“…Recently, it has been demonstrated that, when oak chips were flooded with wine, they would provide 0.135 mg of oxygen per gram of oak chips [14]. In wine aging processes, the oxygen contained in alternative products (oak chips, staves, cubes, etc.…”

Quercus humboldtii(Colombian oak): Characterisation of wood phenolic composition with respect to traditional oak wood used in oenology

“…In oak wood, these compounds are responsible for its hardness and the avoidance of microbiological alterations (Prida, 2002). During wine ageing, they behave as antioxidants thanks to their great ability to consume oxygen (Navarro et al, 2016, García-Estévez et al, 2017. In addition, they accelerate anthocyanin and tannin condensation, which promotes wine flavanol polymerization (flavanoellagitannins) (Cadahía et al, 2008).…”