Many people don’t realize the effort it takes to make champagne corks and the amount of information you can learn from looking at a champagne corks.
Parts of the cork
Raw cork comes from Portugal which supplies 70% of the worlds cork products. Portugal has 720,000 hectares of planted cork forest. Cork is made from the bark of cork oak that are often over 40 years old. A whole champagne cork cannot be cut from the bark of a cork tree because the bark is not thick enough. The dimensions of champagne corks are fixed, they are made from a cylinder of cork 31mm wide and with a maximum length of 41mm.
The cork industry developed a technique to make agglomerated cork by grind cork into granules and then the granules are glued together with a special water and pressure resistant glue to make the cylinder of cork (see the Möet cork below).
The end of the cork that will be in contact with the champagne is made from between 1 – 3 disks of cork bark that are 4mm wide. These disks are then glued onto the bottom of the cylinder. The French often refer to the ground part of the cork as the ‘manche‘ and the discs as the ‘miroir‘, some also call these parts ‘male‘ (manche) and female (miroir).
Shape
The cork from a Non-vintage (NV) bottle of champagne is more of a ‘mushroom’ shape which you can see in the Möet cork below. Producing a cork with no miroir saves money. If you can save €0.1 per cork by producing a simple cork and if the company produces 1 million bottles per year, then the company will save €100,000/year.
If a cork comes from a vintage champagne (above left), then the base of the cork is much straighter than a NV cork. The base of a Champagne cork has a different shape depending on whether it comes from a NV non-vintage bottle or a vintage bottle of champagne.
Vintage corks have been subject to high pressure (6 atmospheres) for many more years more than non-vintage corks. This results in the bottom of vintage Champagne corks being much ‘straighter’ than their non-vintage counterparts.
Labels
The part of the cork inside the bottle should contain the name of the champagne appellation, the name of the producer and in the case of vintage champagne, the year of the vintage.
