Cork v Zork: sparkling wine closure trial commences

The Australian Wine Research Institute (AWRI) has commenced a commercial benchmarking trial for sparkling wine closures. The study will apply a series of physical, chemical and sensory tests to a Premium NV Pinot Noir Chardonnay wine at regular intervals over an initial two-year period.

The study aims to collect key performance data for the eight different closure technologies, including traditional two-disc natural cork, agglomerate cork, screw-cap, crown seal and the Zork SPK Optimum. A survey of Australian wine producers identified the closures that are of most interest to premium sparkling wine producers.

The wine selected for the trial is a tank fermented sparkling wine made from pinot noir and chardonnay, and this will be subjected to the following series of tests at five separate intervals over two years:

• Free and total sulfur dioxide
• Colour development
• Low molecular weight sulfur compounds
• Carbon dioxide retention
• Oxygen transmission rate
• Extraction force
• Sensory descriptive analysis

The AWRI intends to hold a number of tasting workshops in selected regions to showcase the wine’s development under the different closures. This will give small and medium wine producers the opportunity to experience the sensory impact of closure choice firsthand. These workshops will aim to provide a generic overview of the trends seen throughout the trial at different points throughout the life of the trial.