Which cork for wines?

Nearly 90% of wine bottles purchased in France are sealed with a cork stopper. And for good reason: 77% of French consumers consider the cork stopper as a guarantee of quality!

While they are steadily declining, these figures are still higher than what is observed internationally. Especially in the new world, which has long given a chance to alternative sealing methods. Australia and New Zealand have thus abandoned the cork stopper for the screw cap… for more than 40 years! It is also used mainly by our neighbors across the Rhine.

What are the different sealing methods and their respective advantages?

The cork stopper, the tradition

Used to block amphorae in antiquity, cork has the double advantage of being waterproof, but letting a tiny amount of air through. These exchanges between the wine and its environment after bottling allow great wines for laying down to gain in complexity and finesse.

On the other hand, the cork has two disadvantages:

• It presents the risk of transmitting what is called the taste of cork to the wine. We talked about it. This risk, which would affect between 2 and 7% of wine bottles, now seems to be under control. The Atomic Energy Commission has invented a method to wash the cork of all traces of TCA, the substance that causes the cork taint.
• The second drawback is more problematic: global cork production is too low to meet the wine industry's need for corks. A problem that is not close to being solved, when we know that it takes more than 40 years for a cork oak to produce a bark that can be used to cut corks!

The taste of the French for the cork stopper is very closely linked to the marketing of tradition. Indeed, if cork remains the most relevant method of corking for long aging wines, it is absolutely not necessary to preserve wines to be aged for less than 5 years. This explains the confusion in the minds of French consumers: since wines for laying down are quality wines, the cork stopper has become a guarantee of quality.

Caps called technical agglomerate or plastic, a lack of glamor

To deal with the problem of cork production, new “cork-based” stoppers have appeared. These are clogged or agglomerated corks. Their advantage? They have an appearance similar to a cork stopper, but consume less of the precious material. Less expensive, their quality is nevertheless sufficient for corking wines for short keeping.

Their organoleptic quality is relatively good. These corks ensure total sealing and therefore an absence of deviation of the wines they seal.
There would therefore be a logic of quality in the choice of cork: cork for great wines, agglomerated or synthetic corks for others? This would be to forget that there are in fact other types of closures that offer excellent compromises in terms of organoleptic qualities, aesthetics and price!

The screw cap: its only drawback remains its image

The screw cap consists of an aluminum cylinder and a tin or polymer seal. It has several advantages:

• From an organoleptic point of view, it ensures perfect sealing of the bottle. Studies have shown that this tightness is beneficial to lively and fresh wines such as white wines. It allows them to retain this freshness. This foolproof seal also guarantees a wine of uniform quality throughout the cuvée. This does not evolve once bottled. This characteristic is an advantage for wines that are not intended for long aging.
• Its easy handling is another advantage of the capsule: its opening does not require a corkscrew. Once opened, the bottle can be simply closed and reopened. In countries where wine consumption habits are not influenced by century-old traditions favorable to the cork stopper, this simplicity of use is a great success with consumers.
• Note that it also facilitates the storage of bottles. They can simply be placed vertically, without fear of the cork drying out.

These qualities explain the growing success of the screw cap in many vineyards in the Southern Hemisphere, and in a growing number of European farms.

Its main flaw is its aesthetics. Relatively basic, the screw cap lacks the glamorous side that would make it accepted in the demanding world of wine.

However, a bright future is predicted for him. Unless new corking techniques come to compete with it?

The glass stopper, elegance

Since 2004, a newcomer has been involved in the cork battle. The glass stopper makes a place for itself in the sun by taking advantage of its opponents' weaknesses!

Like the screw cap, its seal makes it hermetic and therefore preserves the qualities of freshness of wines for small keeping. Its ease of handling and storage have nothing to envy to its main competitor. What differentiates it from the capsule? Its elegance. This luxurious connotation suggested by the glass resonates with the values carried by the wine.

But this elegance comes at a price: €3 per cork on average, compared to €0.10 per capsule. Paradoxically, this price difference facilitates the respective positioning of these two products. The glass stopper has met with some success for mid-range wines, whose value and finesse justify this investment. It leaves the capsule a marketing space for less expensive wines.

That said, the rapid growth in the number of winemakers embracing glass could quickly drive down the price of this cork. And therefore make it more and more accessible to entry-level wines.

What about the legal representative capsule (CRD), also called "Marianne"?

All bottles of alcohol marketed in France must display a capsule called "capsule congé" or "Marianne". It certifies that the winemaker has paid the taxes on alcohol consumption to the French customs service.

This capsule is superimposed on the cork, or overcap and plays no role in the conservation of the wine! It consists of an aluminum or plastic skirt and a seal: the fillet also called "Marianne". Not being hermetic and therefore does not influence the exchange of air through the cap. Some, associated with the cork stopper of wines for laying down, can be pierced with 2 holes to facilitate these exchanges.