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IVES 9 IVES Conference Series 9 ESTIMATING THE INITIAL OXYGEN RELEASE (IOR) OF CORK CLOSURES

ESTIMATING THE INITIAL OXYGEN RELEASE (IOR) OF CORK CLOSURES

Abstract

Many factors influence aging of bottled wine, oxygen transfer through the closure is included. The maximum uptake of wine before oxidation begins varies from 60 mg.L-¹ to 180 mg.L-1 for white and red wines respectively [1].

The process of bottling may lead to considerable amounts of oxygen. The actual contribution of the transfer through the closure system becomes relevant at the bottle storage, but the amounts are small compared to prepacking operations [2] and to the total oxygen attained during filling.

When corks are inserted in bottlenecks, there is initial oxygen released (IOR) due to the compression exerted to accommodate them in the volume of the bottleneck. Then starts contribution of the transfer between the closure and the glass together through the cork.

The initial release of oxygen is significant compared to the transfer through the cork itself and has been reported around 60% to 70% of the total oxygen ingress in a bottle after the first month and around 90% to 97% after the second, either for corks tested under dry or under wine contact condition [3]. In a study designed for sparkling corks, inerting procedure allowed to reduce the initial oxygen release by around 1.5mg [4]. An identical procedure is used in the scope of oxygen transfer measurements as a preparation for the corks [5].

The current work aims at estimating the IOR of natural corks. Natural corks of a superior grade, 49 mm length and 24 mm diameter, ready for use were purged with nitrogen for 3 months to displace oxygen from cork cells. Then corks were inserted in bottles with controlled bottlenecks and oxygen ingress monitored using the non-invasive methodology [3] for two months. At 64 days, it was observed that corks submitted to the purging procedure released 1.4 mg of oxygen less. In a preliminary experiment purging for 1 month, the reduction of oxygen ingress was around 7% more which suggests that the additional months did not change much oxygen from the cork cells.

The ongoing project aims to consolidate the estimation of the IOR value and to be extended to micro agglomerated cork stoppers.

 

1. Singleton, Vernon L. 1987. “Oxygen with Phenols and Related Reactions in Musts, Wines, and Model Systems: Observations and Practical Implications.” Am J Enol Vitic. 69-77. doi:10.5344/ajev.1987.38.1.69.
2. Reeves, Malcolm J. 2009. “Packaging and the Shelf Life of Wine.” Em Food Packaging and Shelf Life A Practical Guide, de Gordon L. Robertson, 231- 257. CRC Press. doi:10.1201/9781420078459-c13.
3. Ana C. Lopes Cardoso, Chandisree Rajbux, Cristina L. M. Silva, Fátima Poças. 2022. “Modelling oxygen ingress through cork closures. Impact of test conditions.” Journal of Food Engineering 331. doi:10.1016/j.jfoodeng.2022.111105.
4. B. Villedey, S. Callas, A. Descôtes. 2021. Le Vigneron Champenois, 54-69.
5. EXCELL, Laboratoire FRANCE. 2018. “Study of Oxygen Permeability of Technical Corks.” Test Report. Contract No.: N°2017-05- 013 – N°2017-09-001., Merignac.

DOI:

Publication date: February 9, 2024

Issue: OENO Macrowine 2023

Type: Poster

Authors

C. Mariana Machado¹ and Ana Lopes Cardoso¹

1. Cork Supply Portugal, S.A., Rua Nova do Fial, 102, 4535-465 São Paio de Oleiros, Portugal

Contact the author*

Keywords

Oxygen, Corks, Bottle, Wine

Tags

IVES Conference Series | oeno macrowine 2023 | oeno-macrowine

Citation

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