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Murray Almond's "From the Left Island"

Cork Industry To Prove That Things Go Better With CoakTM
© Murray Almond
1 April 2002

Scientists are completing the first trials of a genetically engineered oak tree that is expected to be the savior of the embattled cork industry. The engineered tree, a new sub-genus of oak, produces cork bark, which will be of wine bottle quality, while the tree matures then the tree wood will be used to make wine barrels.

The genetically engineered trees have been trademarked with the name "CoakTM".

Significant Industry Backing
Funding for this research was struggling until a major investment was made by the cork industry into cork research and manufacture. This also has coincided with the Portuguese Cork Industry, APCOR, embarking on a worldwide campaign on the benefits of cork. The cork industry has been on the back foot with industry and consumer reaction against spoiled, or ‘corked’ wine, and the growing popularity of synthetic ‘corks’ and screwcap seals, which are claimed to address the current issues.

The Cork Industry has significantly increased its marketing and technology spending to maintain it’s dominance in this market. It is expected that the combined resources of the oak barrel industry, combined with the multi-million dollar marketing budget on APCOR, will see new emphasis on not only cork, but on oak barrels as well.

About Oak and Coak Trees

The trees used to make wine corks and wine barrels both belong to the botanical genus of Oak 'Quercus'. The cork tree, Quercus suber is a relatively young species of oak, which has very thick bark that can be stripped without damaging the tree. This tree can grow only in a limited climatic range, which restricts prime production to the western Mediterranean (Spain and Portugal).

The oak used for barrels is known either as American white oak Quercus alba with various subspecies grouped as 'American Oak'; or Quercus robur, called Pedunculate, or variously French, English or Russian oak.

The Genetic Scientists have analysed the genes in Quercus suber that provide the thick bark and merged it with various strains of Quercus alba and Quercus robur, to create the Coak Trees.

(source: Oxford Companion to Wine)

Scientists have reported that not only have they consolidated wine barrel and cork production, but have also been able to address the microclimate restrictions that has restricted the cork trees’ growth to the limited area. They claim that any climate suited to oak barrel tress will support Coak trees.

Consistent Wood Flavours
A significant being claimed benefit of the Coak Tree is that the desirable oak characters imparted into wines aged in barrels, particular red wines and Chardonnay, will be able to continue to be imparted to the wine when the wine is in bottle sealed with a Coak cork.

While traditionally the Cork Industry proclaimed that the cork is inert, and does not impart flavours to the wine, others in the wine industry dispute this.

UK Wine Columnist Andrew Jefford notes "It could be argued that what a cork does is to carry on the work (holding, flavour-exchanging, gently oxidising) of a barrel.".

NZ winemaker Michael Brajkovich of Kumeu River Winery agrees in saying "I believe there is no doubt that cork influences wine flavour, and is not totally inert. My evidence for this assertion comes from the experience of "tasting" corks that we purchase. Cork flavour, however, is also extremely variable and has changed greatly over the years as cork production methods have changed." It is this and other factors with cork that has seen Michael take a leading role in the move to the use of Screwcap for seal rather than cork. On the other hand it is not known whether he is aware of the Coak Tree developments.

However the genetic modification technology supporting the Coak Tree would see the development of corks made from Coak bark that would contribute to and enhance the flavours of the matching barrel made from the same genus of Coak tree. Here Cabernet from French Oak Barrels would continue have the French oak flavours enhanced by the Coak Cork, likewise the desirable oak flavours in popular Chardonnay’s would be further enhanced by the flavours imparted by the Coak cork Other flavour enhancements, such as to reflect degrees of barrel toasting, can be factored in.

Predictably the makers of aromatic, unoaked, wines are skeptical of this ‘benefit’ of corks from the Coak trees. The research into a truly inert cork is reportedly still continuing, but scientists are confident of being able to produce an inert Coak cork.

Not a Total Solution
As attractive and far reaching as this research is, it still does has not addressed all the deficiencies ascribed to corks by their critics.

A source reported "the bark of the Coak tree has not as yet been made completely resistant to Trichloranisole (TCA), the compound associated with ‘corked wine’, but we’re working on it, and are confident of progress within the next 30-70 years.

The issue of the variable seal inherent in corks remains an issue. This results currently in bottle variation in long term aging, leaking and random oxidation in wine. This will be probably the most difficult to address as, even with all the enhancements, corks remain to be sourced from the bark of a tree.

The announcement of this research is already of concern in some areas. Ethicists have expressed concern over the whole genetic engineering field, raising issues as to the potential harmful byproduct of this research. "It’s very well to address corked wine and consolidate oak plantations, but what can we be sure that nothing harmful has been introduced?" one insider, who declined to be named, stated.

Nevertheless, those I’ve spoken to of the Coak Tree Initiative stress the positives arising from the research as a further to the acceptance of cork for wine.

Further updates will be discussed as they become available.

This writer remains skeptical and will continue to prefer the consistent, and taint free, screwcap seal is the preferred seal for fine wine, both for short and long term bottle development. This as has been proven over the years with aromatic Rieslings, and increasingly today as more wineries switch to screwcaps.

From the Left Island


© Murray Almond
1 April 2002

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