|Cork is the outer bark of the cork oak tree, Quercus Suber, which grows mainly in the Mediterranean region. The bark is a vegetal tissue composed of an agglomeration of cells filled with a gaseous mixture similar to air and lined with alternating layers of cellulose and suberin. Cork’s elasticity, combined with its near-impermeability, makes it the perfect material for making bottle stoppers, floor tiles, insulation sheets, bulletin boards and other similar products. Because of its remarkable qualities, cork is used in high-tech applications including car engines, dam mechanisms and airport runways. The aeronautics has used cork as a thermal insulator in space shuttles.|
The use of cork as a raw material dates back to Phoenician and Greek times. Cork began to become known all over the world as an effective bottle stopper for wine. In fact, cork is the only material that makes a perfect seal during the ageing of the wine.
Today, cork is a valuable resource for Portugal, representing one of its most important export products.
The cork oak
|Cork oak forests cover approximately 2.5 million hectares across the Mediterranean region and most of them are located in seven countries: Portugal, Algeria, Spain, Morocco, France, Italy and Tunisia.
The tree has a life span of 250-350 years. Each cork tree must be 20 to 25 years old before it can provide its first harvest of cork bark. This cork is known as virgin and has a hard and irregular structure. After the virgin cork has been stripped, a new layer of cork begins to grow.
The first of these layers, harvested after nine years, is called secondary cork; cork harvested after this second stripping is known by the Portuguese word: amadia.
A typical tree produces several hundred kilograms of cork at each harvesting and will survive for many generations. The bark is stripped off the tree in sections by highly skilled men using special axes, a traditional manual skill that dates back many hundreds of years.
Portugal, which produces more than 50% of the world’s cork, has been particularly careful to safeguard this valuable resource. The first Portuguese laws protecting cork oak trees date back to the 14th century. At the beginning of the 20th century, it became illegal to cut down cork oak trees, except for essential thinning or the removal of old, non-productive trees.In a context of increasing concern for the environment, cork remains the only tree whose bark can regenerate itself after each harvest – leaving the tree unharmed. It is truly a renewable, environment