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The importance of oxygen (O2) exposure during wine post-bottling storage to wine chemical and sensory characteristics has been investigated in recent years.Closures used can vary with respect to their O2 ingress properties, making them a major modulating factor of wine post-bottling evolution.It is essential to characterize the phenomena taking place in a wine bottle upon O2 exposure in order to match closure selection and wine composition and style, ultimately delivering to the end consumer the best possible wine.In this sense, achievement of an optimal balance between different volatile sulfur compounds (VSCs) represents a major challenge for the wine industry.The three varietal VSCs of 3SH, 3SHA and 4SMP are thought to contribute positively to wine aroma.Major losses of these compounds can occur upon excessive O2 exposure in the bottle, leading to the generalized use of closures which allows low O2 ingress.However, with too little O2, certain reduetive VSCs such as mercaptans may accumulate, with potentially detrimental effects on wine aroma.In this study, we investigated the influence of three closure types, allowing different degrees of post-bottling oxygen exposure (one natural and Nomacorc synthetic Select 300 and 500 closures), on the evolution of the VSCs 3SH, 3SHA, 4SMP, DMS, DMDS, ethyl mercaptan and benzyl mercaptan in Carmenere wines during 30 months bottle storage.Concentrations of varietal VSCs generally decreased during storage.The two Nomacorc closures generally resulted in higher varietal VSCs content, probably due to lower O2 ingress.Only in the bottle with Select 300 and with the lowest O2 ingress, it was found that the varietal VSC 3SH was still present after 30 months of storage.A minor influence of O2 and closures on the reductive compound ethyl mercaptan was observed.Conversely, benzyl mercaptan (BeSH) showed complex response to varying O2 exposure.Concentration of BeSH initially increased for all closures, with highest levels observed after 6 months in the lower O2 ingress Select 300.A decline was then observed, with the higher O2 ingress Select 500 showing higher concentrations at 12 months.Depending on wine style, BeSH might contribute to either complex mineral attributes or reductive notes.The complex role of oxygen in BeSH formation during wine storage deserves further investigation.