At the NZ Wine Online tasting of New Zealand wines by Escarpment and Quartz Reef at Coast on Wednesday night I sat next to a gentlemen who was absolutely livid that one of the wines had a cork closure. The wine in question was the Escarpment Kupe Pinot Noir 2009 ($74.95), the second most expensive wine of the evening, and Escarpment’s top cuvee. (See Masterclass with New Zealand’s Escarpment and Quartz Reef, Cellarit Wine Blog, 1 October 2011)

Curious why Escarpment’s winemaker Larry McKenna was still sticking with cork in face of what looks like growing consumer resistance, at least in Australia and New Zealand, I asked Larry to explain his reasoning. He believes that for top flight wines, which require bottle ageing to properly evolve, cork is better than screw cap, as it allows the wine to breathe more.

When I got home the latest issue of Decanter was waiting for me on my IPad. Coincidentally, it included an interview with Giaconda’s acclaimed winemaker Rick Kinzbrunner, who told Decanter’s Andrew Jefford that he was unimpressed with what he considers Australian writers’ lack of objectivity about closures.

Like Larry McKenna, Kinzbrunner uses both cork and screw cap, and likes both for different wines. He was appalled by the response of one writer upon hearing that Giaconda’s nebbiolo is sealed under cork: “Now surely if there’s one wine that needs cork, it’s nebbiolo. The vitriol I got after that! ‘No, I’m not interested in your wine if you seal it with a stupid piece of bark.’ There’s this insane preference for screw caps in Australia; and I don’t think it’s objective.” (The Decanter Interview: Rick Kinzbrunner by Andrew Jefford, Decanter November 2011)

In Australia, Kinzbrunner is not exactly a lone ranger among fine winemakers when it comes to maintaining a preference for the cork closure.

Jasper Hill’s Ron Laughton told Langton’s Andrew Caillard that from an organic/biodynamic point of view, he is concerned about the health consequences of wine staying in contact with the plastic seal in the metal screw caps : “Metal (screw cap) seals require an internal soft compound to actually seal against the glass bottle neck…The manufacturers say this compound is food grade, but there have been many contaminant scares within the food industry in the past. I don’t like the idea of my long living wines being in contact with plastic for maybe twenty years and what may leach out of the food grade plastic over time.” (To Cork or Not to Cork: That is the Question by Andrew Caillard, Langton’s Magazine)

Peter Althaus of Tasmania’s Domaine A, one of Tasmania’s best wineries, clearly articulated his reasons for sticking with cork in his newsletter:

We all know that wine ages differently under cork compared to that of screw cap. It’s a living thing and needs to ‘breathe’. The cork acts like a permeable membrane between itself and the big wide world. Over years the wine slowly develops and ages. All great wines need to age. That’s why we cellar wine – to allow it to develop in something special The screw cap can can slow the ageing process of wine because it breathes less. Wines under screw cap can take many more years to develop than under cork. That may be fine for some but an ’89 Petrus would be a very different wine today if were sealed under screw cap.

While acknowledging that screw cap eliminates the possibility of cork taint, Althaus goes on to say: “The closure can get damaged easily and then leak, and there have been reports of excessive sulphur levels which cause ‘reductive’ characters in the fruit and make the wine smell ‘rubbery’ or ‘eggy’.” (Tete A Tete, Volume 15, July 2010)

But the debate about whether a cork closure helps the wine to age better than a wine sealed under screw cap is far from settled. Matt Harrop of Shadowfax Winery told Caillard that he is convinced that “under screw cap wines age slowly and consistently. They retain brightness and youth for longer. We are now seeing wines age as they are supposed to. Not in the random, haphazard manner of cork bark…The ridiculous argument that screw capped wines will not age is wrong. Not ageing is a good thing. Rapid ageing is not a good thing.”

Fortunately, Australia’s and New Zealand’s early and quick adoption of the screw cap has played a pivotal role in forcing cork producers to lift their game. Recent investment in new technology, processes and quality control have resulted in much better and more reliable corks. Althaus said Domaine A imports corks directly from a supplier in Spain, and less than 1% of Domaine A wines suffer from cork taint.

So, the debate over cork versus screw cap rages on. But given that the majority of fine wines world-wide are still sealed under cork, I think you do yourself a real disfavour if you don’t keep an open mind!

Merrill Witt, Editor