Comparison of the effect of 8 closures in controlled industrial conditions on the shelf life of a red wine

Aims: The management of O-2, CO2 and SO2 at bottling and the choice of the closure are two key factors of the shelf life of wine in bottles before bringing them to market. The impact of four screw caps, two synthetic and two technical corks was evaluated on a red wine of Merlot/Tannat. Methods and results: Analytical monitoring (O-2, CO2, SO2, aphrometric pressure, L*, a*, b*) was carried out during 538 days of storage at 20 degrees C. Two sensory analyses at 10 and 17 months completed the study. The wine was bottled with an average total oxygen content of 2 mg/L. The heterogeneity intra and inter procedure was controlled, including for the dissolved carbon dioxide content. Conclusion: Unlike closures with highest OTR, the two technical corks and the two screw caps with Saranex seal, harboring the lowest OTR, matched with the wines exhibiting a low total O-2 content at equilibrium (from 4th to 18th month), with more free SO2 and less changed colour. However this OTR gradient (5 to 67 mu g/d) observed through the physicochemical analyses was not necessarily confirmed by both sensory analyses performed. Significance and impact of study: This study puts into perspective the impact of OTR closure on sensory characteristics evolution of wine consumed during the first two years, especially when the total oxygen at bottling exceeds 1.5 mg/L.