Definition: Cork - history

Topography of cork: "the bark tree" is what the Greeks called the cork oak in ancient times. There are several species of cork oak, but the most common is Quercus suber, hence the name "cork oak forest" to refer to stands of cork oak trees.

This tree has grown naturally in the western Mediterranean basin for a very long time: 93% of the world's cork production comes from Portugal, Spain and North Africa, with the rest coming from Italy and the south of France.

Why use cork for wine stoppers?

Since its "rediscovery" by Dom Pérignon at the end of the 17th century, the cork stopper has evolved considerably to meet the demands of modern bottling. To date, no other material, natural or synthetic, offers the same advantages as cork for sealing: elastic properties, low density (a cork cell contains 89% gas), liquid tightness, and the pleasure of uncorking. All these characteristics make cork, today as in the past, the natural and inseparable partner of wine.

The cork comes from the cork oak, which grows in forests known as "suberaie", from the Latin name for the cork oak (Quercus Suber). This tree is unique in that it only develops its bark in the climatic zones of the Mediterranean basin (the Iberian Peninsula, Corsica, Var and Sardinia, and the Maghreb countries). It takes more than 30 years before a tree can be harvested for the first time. Known as "de-corking", this first harvest takes place between mid-June and mid-August. It is a very delicate operation that consists of "lifting" the male cork (or first bark) without damaging the protective surface (the mother), so that the latter can reproduce approximately 9 to 12 years later (depending on the region) a so-called "female" cork that will be used for the manufacture of corks.

The main sources of supply for cork manufacturers are Spain (Extremadura, Andalusia, Catalonia), Morocco, Sardinia, Corsica and the Var region of France. The harvested cork is then stored in a yard for at least a year to "rest". It is then boiled for the first time to be prepared, i.e. sorted according to thickness and quality, and then placed in numbered bales.

This cork is then boiled a second time to soften it and prepare it for processing. The bales are finally left to rest in a damp cellar for about a week.

Once this preparatory work has been completed, each cork plank is cut into strips of equal width to the desired length of the future cork, and each strip is perforated with a punch. The semi-finished cork is then trimmed, i.e. levelled to the same length.

The next step is pre-sorting using compressed air to classify the corks into different quality grades. After a few days of rest, depending on their quality, the corks are washed using a specific process and dried by rotation and ventilation.

After another sorting stage using an optical camera, the corks are marked, either by branding or with ink, satin-finished with an elastomeric lubricant and packaged in heat-sealed bags under vacuum and SO2, before being placed in boxes and shipped to the customer.

Each stage of production is subject to systematic quality control. While the essential quality of a cork is its ability to remain unnoticeable in order to preserve the natural qualities of the wine, the manufacture of corks relies on specific expertise combining in-depth knowledge of the raw material, cork, and constant optimisation of production processes.