Because not all cork closures have exactly the same properties, it is important to understand their specific features. This will allow you to choose the type of cork closure that offers the perfect match for the standards you have set for your wine.
Whether still or sparkling wines or wine-based spirits, each one has its own type of cork closure.
Cork closures for still wines
For the still wine category, four types of cork closure can be used: natural cork closures; colmated cork closures; agglomerated closures; and technical closures.
NATURAL cork closures
The natural cork closures are cut out straight from the planks of corkwood extracted from the cork oaks. The process is known as punching. The corks are therefore in one piece and there are different categories. They are graded depending on their appearance, from 6 to Superior for the finest.
COLMATED cork closures
Colmated cork closures are made from natural cork closures whose lenticels have been sealed with cork powder derived from the manufacturing process and glue in order to maximise performance.
Closures made from cork granulates
Made from quality cork granulates, agglomerated closures are mostly used for still wines designed for relatively early drinking.
The granulates are obtained from offcuts during the punching process, which are then crushed. They can vary in size, from the minutest (micro grain) to the largest (large grain). They are then assembled using a food-grade glue.
Technical closures emerged on the cork closure market a few years ago. They are made from cork granulates and natural cork discs.
They provide the substantial sealing capacity of agglomerated closures whilst ensuring the wine is in contact with natural cork.
Which cork closures are suited to sparkling wines?
The specific features of sparkling wines require usage of a specific type of cork closure.
Cork closures for sparkling wines are therefore formed of:
- a cylindrical body made from cork granulates;
- natural cork discs cut from the thinnest planks of cork that run perpendicular to the growth layers. One or several discs are then glued to the body. These are the discs that are in contact with the wine.
The closure only takes on its final mushroom shape, typical of Champagne, once it has been partially inserted into the bottle.
A closure unlike any other for fortified wines
Bottles of fortified wines are opened and closed more often than other bottles, making it essential to equip them with a suitable closure.
So for the fortified wine category, a plastic or wooden cap is mounted on the cork closure.
The different types of cork closures available make them suitable for every category of wine: still, sparkling or fortified. Carefully selected both for their technical properties and their appearance, cork closures add the final touch to the bottling process.