Closure oxygen ingress can play a crucial role in the development of wine in bottle. By managing this oxygen ingress, it is possible to modulate the aromatic evolution of a wine but also to avoid reduction or oxidation. But to do so, the total closure contribution must be taken into consideration. This contribution does not only rely on the oxygen transfer rate (OTR). Closure oxygen or outgassing, which corresponds to the release of oxygen contained in the closure, is a physical phenomenon that also contributes to the total closure oxygen ingress. The total closure oxygen ingress corresponds in fact to the sum of the OTR and the outgassing.

We have developed a fast and reliable method that allows measuring accurately this closure oxygen ingress valid for natural corks, cork-based stoppers and mono or co-extruded closures. This method provides the winemakers with means to assess the performance of their closures. On top of that, this method also allows evaluating the cork to cork variation within batch or across batches. As a matter of fact, closure selection can be better achieved based on the technical and qualitative objectives defined by the winemakers.