You are here: interpack Magazine. Packaging sustainably.

Articles

Cork: Alternatives are No Longer Taboo

View large image in photo gallery

For many centuries cork has been considered the only conceivable lid for wine. For many wine lovers it continues to be one of the epitomes of wine culture. If there was not the problem of the corky taste: not least for that reason cork had to increasingly compete with other materials as a traditional fastener – and has clearly lost ground.

As early in the 5th century B.C. the Ancient Greeks are reported to have closed their amphoras with elastic corks. 2,000 years later Pierre Pérignon (1639 - 1715) made use of this knowledge and replaced the wooden stop of sparkling wines with corks in order to prevent release of the pressure of the carbonic acid forming in the bottle during the second fermentation. Famous wines such as the most renowned Bordeaux, Port, Constantia and Commandaria were the first wines sold in bottles - rather than barrels - and all corked up. However, the breakthrough for this method of selling and corking up wine only arrived in the 19th century when industrialisation made bottle production cheaper and the demand for corks soar.

Portugal World Market Leader

Cork is a natural product and made from cork oak bark. Today cork oak is grown in Algeria, France, Italy, Morocco, Portugal, Spain and Tunisia. The European cork industry produces approx. 340,000 tons of cork worth about EUR 1.5 billion. On a global scale the market leader is Portugal with 31 % of the cork oak stocks. 51% of global production (190,000 tons) comes from here.
However, cork oaks are initially not suitable for producing first-class bottle corks: The virgin or male cork first formed by the tree over the first few years cannot be used for cork making. It is carefully peeled off. From the age of 20 to about 150 the female cork is peeled off the trunk every ten to 12 years - only then does it have the strength and quality required for making quality bottle corks. The output can therefore not be extended at short notice. And this might be one of the issues for natural cork these days. Not adhering to this peeling cycle and debarking trees too frequently affects cork quality.

Inimitable "Pop"

Now as in the past many wine drinkers use natural cork to seal their wine and sparkling wine bottles. Even the cork’s inimitable "popping" sound is part and parcel of the stylish bottle opening ritual for many - provided there was not that problem of the cork taint, which now occurs with five to ten percent of corks causing major economic damage every year. The corky taste is caused by micro-organisms which can penetrate into the pores of the cork plates while being stored after peeling. There they produce such substances as trichloroanisole (TCA), which can start affecting the taste during the subsequent sterilisation of corks. Portuguese cork industry reports that over the past ten years more than EUR 400 million have been invested in the latest technical developments and quality management in order to combat this corky taste. Only a few years ago cork used to be the brown gold of the country selling like hot cakes - now the Portuguese cork industry is worried about its existence.

The Alternatives: Plastics, Metal, Glass

After all, the world of cork began to totter a few years ago when discussions about the pros and cons of natural cork started. To counter the cork taint many wine growers have extended their ranges to include plastic alternatives. Furthermore, plastics are a very inexpensive alternative. Additionally, plastic corks have the advantage that bottles can be stored horizontally or vertically without affecting the quality of the wine. Maturing of the wine is not possible. Bottles sealed with natural cork can breathe and mature but should only be stored horizontally to prevent oxidation caused by oxygen intake and wine spills through dried-up corks.

Other alternatives include screw caps allowing the bottles to be resealed easily keeping wines fresh for an extended period. Of the approx. 17 billion bottles of wine produced in 2008 worldwide, roughly 2.5 billion are said to have been sold with screw caps. However, screw caps still suffer from a comparatively poor image since they have for a long time now predominantly been used for simple wines. On an international scale it is primarily Australia and New Zealand that are pushing screw caps today. Some retail chains now even demand the use of screw caps or other alternatives from their suppliers to avoid the problems caused by corked wines.
2004 saw the Alcoa company launch a new glass cap - the "Vino-Lok". A glass "cork" ensuring tightness and a safe lock with the help of an Elvax gasket. The output of this resealable cap has risen from two million in the first year to over 20 million in 2008. It meets with consumer acceptance and is employed in both the standard and high-end or exclusive segment.

WWF Warning

The World Wide Fund for Nature (WWF) and other environmental protection organisations have warned of a collapse of the cork oak ec-system. Parts of Portugal, in particular, are considered extremely endangered if the market increasingly takes to alternatives. Critics counter this argument by saying that demand for cork is not expected to disappear completely, all the more as this material is also in use as a wall-cladding and floor covering material. Nevertheless, the wine sector is currently experimenting with other alternatives and the former taboo no longer seems to apply; the dominance of cork for several centuries seems to have finally reached its end.