Can oak stoppers be made in China? The history of the oak cork of the cork

However, cork stoppers had not yet become mainstream in those days. At that time, the most common stoppers used as wine jugs and jugs were made of fire paint or plaster, and olive oil was dripping on the surface of the wine (to reduce the contact of the wine with oxygen). In the Middle Ages, it was clear that cork was completely abandoned.

Oil paintings of the time depicted wine jugs or bottles stuffed with twisted cloth or leather, sometimes with wax added to ensure a tight seal.

It wasn't until the middle of the 17th century that cork corks were really associated with wine bottles. At that time, as an alternative, ground-glass closures also appeared from time to time in order to fit different bottlenecks, which were used for a long time. Until 1825, these glass stoppers were the stopper of choice.

Eventually, the stoppers were discarded, because there was little else to do but break the caps if they were to be removed. Before cork stoppers were widely used as practical closures, there was a question of finding a tool that could easily drill into the oak and remove the cork. The first mention of a similar corkscrew was in 1681, when it was described as "a steel worm used to pull a cork out of a bottle".

This hand tool had been used for the removal of bullets and soft fillers from firearms 50 years earlier. It was first known as the bottle drill and was not officially called the corkscrew until 1720.

Oak stoppers are bottle stoppers made from the wood of the oak tree. In the 5th century B.C., the Greeks sometimes used oak to plug wine jugs, and under their leadership, the Romans also began to use oak as a stopper and seal their mouths with fire paint. The process of making an oak stopper is divided into:

Peeling, air drying, boiling, material selection, strip cutting, molding.

"Quercus cork" is the botanical name for a slow-growing, year-round evergreen oak that grows only in certain western Mediterranean regions. The tree requires a lot of sunlight, a perfect combination of low rainfall and slightly higher humidity, and its bark quality and thickness vary depending on the specific environmental conditions of the place where it is grown.

Thanks to the soft protective layer of bark and especially the insulation from fire, the oak grows continuously. Many trees die because they lose their bark because the bark carries the necessary energy, the sap, to the entire tree. This soft oak has two layers of bark.

The inner layer of bark is alive and is the basis for the growth of new bark every year. When the old bark grows outward and dies, the new bark takes on the responsibility of continuing to grow. The outer layer of dead bark can be peeled off so that it does not hurt the tree, but be careful not to pierce the inner layer of living bark.

The first harvest of the tree is not possible until it reaches 25 years of age. The oak harvested this time is irregular in size and density, making it unsuitable for use as a wine stopper, and is often used as a flooring or good insulation. After 9 years, the tree can be harvested again, but this time the harvested oak is still not good enough to be used as a stopper.

Until the third harvest, when the tree was 52 years old. This is where the size, size and density of the tree make it a suitable material for wine stoppers. An oak tree can usually be harvested 13-18 times in its lifetime.

With the help of a sharp axe, the soft oak can be peeled off by hand, and the bark is then stacked for weathering. Trees that have been stripped of their bark are carefully marked with marks and numbers so that future harvesters know which tree can be harvested again.

Once transported to a factory in Portugal for processing, the oak is stacked again and air-dried for up to 3 months. Proper humidity is essential for the elasticity and compressibility of oak. After air drying, the cork is soaked in boiling water for 90 minutes, both to sterilize and to flatten out its curved shape.

The cork is then left for 3 to 4 weeks to allow it to reach the desired humidity. The materials are then arranged in strips and corked according to the size and shape of the bottle. In this punching process, it takes a lot of dedication from the puncher to produce the highest quality product.

The head and body of the stoppers are then polished so that all stoppers have a consistent length and diameter. It is important to note that the thickness of the bark determines the diameter of the stopper, not the length of the bark, so the tree's growth rings appear to be implanted longitudinally. The corks are then washed and dried, and most of them are bleached with chlorine or hydrogen peroxide, which not only disinfects but also removes any remaining impurities.

There are also some that do not need to be bleached, depending on the needs of the winery. The corks are graded according to quality and are also marked with the name of the winery. Finally, the surface of the stopper is sprayed or coated with silicone, paraffin or resin to make it easier to insert into the mouth of the bottle and also to improve the sealing of the glass bottle.

Then, pack it in a plastic bag and it's ready to ship.