Which cork is best?

  • Friday 30 January 2009

As a respected wine publisher and author, ROBERT JOSEPH spent years highlighting the faults caused by poor closures. Now he’s a wine producer, how would he decide upon natural cork, synthetics or screwcaps to seal his bottles?

Ten years ago, if anybody had predicted that I would one day lose sleep over the best way to seal a million bottlesof wine, they might as well have suggested that I’d be thinking of methods to steal the stuff. But a lot can happen in a decade.

Back in the last year of the 20th century, I divided my time between writing articles and books on wine, and chairing wine competitions in London and Asia. It was then I started to metamorphose into a dangerously geeky creature: a person for whom wine closures would be a specialist subject. It started gradually, as I began to notice how many wines in the

competitions were tainted with TCA (2,4,6-trichloroanisole) by bad corks, and a recognisably ‘flat’ character in wines stoppered with a then-recently developed and widely used ‘technical closure’ called Altec (made of tiny cork granules and touted as being totally free of TCA).

In those long-distant days, screwcaps were still more or less restricted to the cheapest, most basic wines. The talk was all of synthetic corks, which were predicted by some to replace the real thing completely. But there were also suggestions that these closures caused wine to age prematurely and broke corkscrews. And then there were the spin-doctoring skills of the larger cork manufacturers who not only brazenly denied that TCA taint was a problem, but also seemed to be associated with scaremongering rumours linking

alternative closures to cancer.

I remember a number of thoughtprovoking moments. There was the encounter with a brilliantly youthful 25- year-old screwcap-sealed Pewsey Vale, Eden Valley Riesling which proved thatwhite wine, at least, could age perfectly well without a cork. There was the wellpreserved 1907 Piper Heidsieck rescuedafter 86 years on the ocean floor during which time it presumably didn’t do much ‘breathing’ through its cork.

And then in 2000 there was the blind tasting of wines produced by the Union des Grands Crus de Chablis at which low-level taint or random oxidation caused one of Michel

Laroche’s wines to taste uncharacteristicallyflat and dull – and drove him to use screwcaps for his grands crus. The more I thought about closures, the more fascinated and frustrated I became by the lack of available information. So, in a moment of madness (I really did have better things to do with my life), I started a non-commercial website, corkwatch.com, to impartially cover news about all kinds of natural and alternative closures.

Over its nearly five-year lifespan, the site raised issues such as the blame that corks unfairly received for TCA-taint from newly treated timber in wineries and cellars. It looked at rubbery ‘reduction’ odours from screw capped bottles (almost always a result of winemaking not being adapted to the closures), and scraped the surface of the mysteriously short-lived white Burgundies of the late 1990s (probably caused by a number of factors including insufficient use of sulphur and faulty corks). It covered the threats to Iberian

wildlife caused by the move away from natural cork, and the stories of unfortunate

producers such as Elio Altare in Barolo who lost an entire vintage to tainted corks.

Perhaps most usefully, its existence also prompted me, in the summer of 2003at the Vinexpo wine fair, to set up the first blind comparative tasting of olderwines sealed with corks and alternatives. My experience at that tasting – where the alternatives, including a 1983 Beyers Truter Paul Sauer from South Africa generally showed well – left me with no patience for the four-legs-good, two-legsbad absolutism of the pro-cork and proscrewcap lobbies.

To talk generically about ‘cork’ is like referring to ‘beef’ or ‘claret’. There are 700 cork manufacturers in Portugal alone; some are far more conscientious than others. Synthetic corks vary too, as indeed do screwcaps, though this last category seems to be more homogenous than corks.

Some wines suit some types of closures better than others. Any discussion of the way a wine improves with time under a cork, for example, is of absolutely zero relevance to a Pinot Grigio or a rosé that’s intended to be drunk within weeks of its purchase. On the other hand, despite my deep misgivings about the unreliability of corks, I’d still rather not unscrew a Romanée-Conti.

Reality check

In 2005, after the sale of the International Wine Challenge and my retirement from my role as its co-chairman, these questions ceased to be hypothetical. With former flying winemaker Hugh Ryman and label designer Kevin Shaw as partners, I became involved in the business of creating, branding and packaging some entirely new wine ranges.

Working with producers in France, Spain and Italy, our self-appointed role was, and is, to come up with wines that look and taste good and sell in reasonable volumes in a wide range of countries, for the most part at under £7 or the local equivalent.

Hugh and I had mixed, and in some cases, differing views on the subject of what we would put in the necks of our bottles. We had to consider a wide range of criteria. Performance – which, for us, meant consistency and an absence of taint rather than long-term ageing – was crucial, but we also had to consider price. When you are earning €3 a bottle, it makes no sense to spend a sixth of that sum on a top-quality cork, or the new glass Vini- Lok stopper which might score highly in the next category: aesthetics.

Then, of course, there are environmental factors, ranging from preserving Portuguese flora and fauna to carbon footprints. For some people, these last considerations are sufficient in themselves to tip the scales in favour of natural cork, despite its shortcomings. And I respect that view, just as I respect the decision by a biodynamic producer like Vanya Cullen in Australia to seal her bottles with screwcaps in order to allow the flavour of her terroir to get into the glass without any interference from a closure.

But it’s not that easy. UK supermarkets, for example, don’t want natural cork in our kinds of wines, because they don’t like having to deal with bad bottles. Ever since they switched to synthetics and screwcaps, the number of returns has dropped dramatically. As the price of cork has risen, getting even half-decent ones for much less than €0.25 is almost

impossible.

Reliable (synthetic) Nomacorks cost €0.05–0.07 by comparison, while screwcaps cost €0.12. The latter, however, need no capsules, so ultimately work out at around the same cost as the synthetic closure. Until recently, it was generally agreed that synthetics offer very short-term prospects for wine, but Nomacork’s manufacturers now guarantee their closures for three years – rather longer than some of those white Burgundies survived.

For our Greener Planet organic wines, we decided, with the encouragement of the US retailer who is our biggest customer, to use natural corks. Corks have certainly improved in quality overthe last few years, but random oxidation is still a problem and any suggestion, such as the one made in a recent BBC2 programme on UK television, that TCA taint is a thing of the past is, frankly, laughable.

I did not, for example, appreciate opening a nastily corked bottle of Greener Planet in the tasting room of one of Britain’s biggest supermarket chains. Happily I had a perfectly sound

spare bottle to hand, but I couldn’t help wondering how many of our customers have similar disappointing experiences when they pour this wine.

Ideally, we’ll switch from cork to Diam, the reliable and relatively environmentally friendly successor to the awful Altecs that so used to bother me a decade ago. But I can’t help noticing that Bonterra, my favourite US organic brand, has recently moved from cork to screwcap.

That decision may help us to persuade our US customers to let us use screwcaps for our wines, but so far they have more or less insisted on synthetic corks for both reds and whites, and withsales of more than 750,000 this year, we’ve had absolutely no complaints.

I suspect that one of the attractions of these synthetics, apart from their reliability, is that for the casual corkscrew user, they may actually pass for natural cork, and in the US, this still seems preferable to either screwcap or Diam. But, I’d be surprised if this didn’t change, and if screwcaps didn’tbecome as acceptable in the US as they are in Britain.

Bag-in-box was, after all, similarly slow to take off on the US west coast, but now has a huge following. Today we’re looking at other forms of closure and, indeed, bottle. The Vive la Revolution and Greener Planet Sustainable wines we’re just launching both come in a low-carbon footprint, easily recyclable, one-litre PET bottle which has a built-in PET screwcap and a guaranteed two-year shelf life. I’m not for a moment suggesting that these, any more than screwcaps, are the ultimate answer; they are merely another stage in wine evolution.

After countless false starts in Portugal, new NASA technology (see above) may finally get rid of TCA taint from cork, but I still doubt that millions of new wine drinkers in China and India are all going to buy corkscrews. The challenge lies in finding ways to package wine that are good for both the liquid and the planet. And for the Portuguese farmers to come up with profitable alternative uses for their tree bark.

How the Cork industry is fighting back - By David Bird MW

The Portuguese cork forests have been alive with activity of late, as the big cork producers transform their methods of production in a bid to reduce the risk of corked bottles by at least 80%. Oeneo has introduced the Diamprocess, in which supercritical carbon dioxide (also used for decaffeinating coffee) is used as an efficient solvent, being halfway between liquid and gas.

This is high-tech stuff, with Oeneo’s new production facility in Spain resembling a

NASA laboratory more than a cork factory. At Amorim, most processes are unrecognisable compared with 10 years ago. Quality procedures have been overhauled, starting in the cork forests. Here, the lowest part of the bark near the ground, which can harbour the moulds that play a part in the production of the musty taint, is no longer cut away.

The journey the bark makes by road has been dramatically reduced by building new factories close to the forests in south Portugal. Here, the bark is stored only on concrete or stainless steel, never touching bare earth. Before it is used, the bark goes through a rigorous selection process, with pieces that are too thin or rough being rejected. Chosen pieces then go into a boiling bath where hot water is circulated through stainless tanks.

After a short storage period – much shorter than under the old regime – the pieces of bark are cut and rejected if they show the slightest hint of a greenish stain. Rejected wood goes into building material for insulation, flooring tiles, shoes, engine gaskets and even as fuel

for the furnaces that heat the cork factories. Nothing is wasted.

The punching of the corks is still done by hand – the most effective way of ensuring that corks are taken from the best part of the bark. Machines have been trialled, but nothing can match an experienced human hand and eye. It’s long been known that rogue TCA can be vapourised by steam, but producers couldn’t do this without distorting the cork. This has now been achieved with the ROSA process, unique to Amorim, which targets any residual

TCA that might have got past the multiple selection processes.

The Cork Supply Group and Alvaro Coelho & Irmãos have introduced similar steaming systems that can take TCA below the limit of detection. The result is that large producers can now all but guarantee the corks they supply will be essentially free from cork taint. But there are many small companies that are still working to the old standards – hence for now, caveat emptor.

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