The impact of closure type and storage conditions on the composition, colour and flavour properties of a Riesling and a wooded Chardonnay wine during five years' storage

This paper presents the results from an investigation to assess the development of a Riesling and a wooded Chardonnay wine over five years following the imposition of several treatments at bottling. The wines were bottled under a screw cap closure, two different natural corks, a synthetic closure and in a glass ampoule. In addition, the effect of storage orientation was investigated. The bottled wines were stored under controlled temperature and humidity conditions. Various analyses were carried out on replicate bottles from each treatment, including sulfur dioxide and ascorbic acid concentration, sensory analysis of appearance and aroma attributes, and spectral measures. The largest treatment effect resided with the nature of the closure. Wines sealed with the synthetic closure were relatively oxidised in aroma, brown in colour, and low in sulfur dioxide compared to wines held under the other closures. A struck flint/rubber (reduced) aroma was discernible in the wines sealed under the screw caps or in glass ampoules. Wines sealed under natural bark corks in this study showed negligible reduced characters. The bottle orientation during storage under the conditions of this study had little effect on the composition and sensory properties of the wines examined.