Freeimages.com © Rainer SchmiedMore and more often we find a wine bottle on the shelf that does not have a cork stopper as we are used to. Is sustainability the reason why the wine industry switched to metal closures with purpose to protect the cork oaks? Not quite, because you don’t have to fell a tree to get the cork.One of the aspects, why metal or in some cases plastic and glass closures are becoming increasingly popular in the wine industry, is the cheaper price. Furthermore it´s the fact that the main reason of musty smelling wine can be a cork. The potential perpetrator of this odor is the substance TCA (trichloro anisole).TCA in a cork may develop during processing process of washing. The trichlorophenols are formed through a reaction of the phenols contained in the cork with substances containing chlorine, possibly from detergents. The whole process is encouraged due to the mold cultures such as Trichoderma that may be present in the cork.Are the cork resources at risk? In order to harvest the cork bark, well-tried techniques are used that promote the regeneration of the tree. In this sense, this process supports the conservation of the cork oak forest. The bark is first harvested from trees that are 25 years old, followed by further cycles after 9-13 years. In average, a cork tree reaches usually the edge of 200 years.Because of their thermal and fire-retardant characteristics, the cork oaks are not easily inflammable, so they are often spared during fires in the summer months.Some facts about the cork The cork bark removed from the trunk contributes to the fact that the cork oak draws more CO2 from the environment than an unpeeled tree. Consequently, cork has an excellent ecological balance.Most of the world’s reserves of cork trees are in Portugal and 50% of them come from a picturesque region called Alentejo. Many residents from this area also work in the cork industry. The other larger reserves are in Spain. Italy, northern Africa (Morocco, Tunisia, Algeria) and France also have some cork oak forests and locally based cork processing.Cork can be recycled and in the case of wine stoppers to 100%. Even if it is not a most common process in northern countries, you can participate in the cork recycling process in the wine countries where cork is also harvested. The restaurants, as well as private households, collect the cork and pass it on for further processing.In addition to its classic application in the wine industry, cork is also used in many other areas. It is also known as a building material, furniture or household article, footwear and fashion item. Even the modern space industry benefits from the special properties of cork.Due to its extremely good thermal insulation properties, cork is used in the critical components of the spaceship, which could catch fire at the high temperatures (over 1000 ° C).Cork oak forests form a unique natural ecosystem with biological diversity. They provide a habitat for over 100 plants and around 150 animal species – including a great number of rare birds, mammals and reptiles. Among the cork oak forest inhabitants there are some animal species, such as the Iberian lynx, which are critically endangered.unsplash.com © Zdenek MachacekCork harvest The job of forest workers who peel the bark from the cork oaks require a finesse to avoid injuring the tree trunk. This knowledge is not acquired in school, but passed on from generation to generation.The cork peeler splits the cork bark with its specially shaped ax and brings it to burst. As next, the bark is carefully opened from the top to the bottom, with help of the rounded ax tip. The long semicircular parts are then removed from the tree and the terracotta colored trunk shows its nudity.