The process

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Stripping
It consists of the extraction of bark from the cork oak, i.e., the cork that covers its trunk. Regular extraction of cork from the tree allows the healthy growth of the tree throughout its life-cycle, which usually lasts from 150 to 200 years.

Stabilisation
During a 6-month drying period, the cork planks are exposed to air until they lose their internal moisture content.

Boiling
The cork planks are boiled in clean water for one hour. This process is intended to disinfect the cork and expand its lenticels, so that it becomes more flexible, voluminous and soft.

Sorting of cork planks
After boiling, the cork is dried and left to rest for three weeks. Then, it is separated according to its thickness and quality.

Punching of cork stoppers
The cork boards are cut into strips with the appropriate width for the production of cork stoppers. The stoppers are punched out of these strips, and their size is subsequently rectified using specialised machinery.

Selection
The stoppers are visually inspected and separated by category, by highly qualified staff and automated optical readers.

Cork stopper processing
Once sorted, the stoppers undergo a process of washing and disinfection. The most popular method consists of washing the stoppers in an aqueous solution of hydrogen peroxide.

Marking and Packaging
After the final selection, the stoppers are marked according to the customer’s specifications. Following the marking, the stoppers are coated with silicone or paraffin, so they can be easily inserted and removed from the bottle. The stoppers are then packed in plastic bags filled with SO2 and sent to the bottling facilities.