Contribution to the characterization of cork's use-life

Oxygen permeability data is relevant for selecting wine bottle closures, but the impact of wine contact, temperature, and time use has not yet been explained. Market available stoppers were analysed for oxygen ingress over time in stoppered bottles, under different temperatures, with and without contact between the cork and wine simulant. The Weibull model described well the oxygen ingress. Differences were found between cork types, in long-term oxygen pressure values and ingress rates. The temperature effect followed an Arrhenius behaviour, with statistical significance only for micro agglomerated corks. Micro agglomerated corks exhibited slower initial oxygen ingress but higher long-term oxygen ingress than natural corks. Principal Component Analysis (PCA) showed that factors related to the bottleneck-cork interface contributed more to the variance of the system than the cork type. Liquid contact reduces oxygen ingress rate around five times. The temperature impact in the oxygen ingress was lower for natural corks than for micro agglomerated corks.