Knowledge - Screwcaps for wine?

Suddenly screwcaps are all the rage on bottles of wine.  And what about these plastic corks? Are we really expected to believe that these wines are “good” wines.

What is the real story here?

For 300 years the cork has been the closure of choice. It does the job – it is airtight, yet has a magical property which allows wine to develop in the bottle as it ages. But it has never been 100% reliable and has a problem of occasionally tainting wine with Trichloroanisole (TCA) – so called “corked” wines.                       

As wine consumption grew in the 1980’s “cork taint” became more noticeable (more wine, more bottles, more “corked” bottles). Although people who make cork will admit to 2-4% of bottles having this problem, winemakers consider this to be too high, so many look a “more reliable” alternative. Currently plastic corks and screwcap tops are the favourites.

With more and more wine being drunk, there’s plenty of incentive to get things right. The Australian Wine Research Institute has found that although plastic corks are good for young fresh wines, they have too high a permeability to be of value for keeping wines for any length of time. As a result, Plastic corks are mainly to be found in inexpensive wines intended for drinking soon after bottling.


Screwcaps are really the main alternative to cork. The switch is happening throughout the world, with winemakers in New Zealand leading the way, promoting the screwcap as the perfect closure. In 2005, 92% -  almost ALL of New Zealand’s wines - had screwcaps rather than cork.

Its main advantages, its supporters claim, is that it is inert, creates a perfect seal and is impermeable and thus perfect for long term keeping (cellaring) of wine. In the main, these claims are true, although they have fuelled other wine debate – “Does wine need oxygen to age” – (but we won’t concern ourselves with that today.)

If so, why isn’t everybody switching to them?

Several reasons. Firstly , there is a very big cork industry that is fighting back and at the same time spending lots of money to eradicate cork problems. Secondly, not everyone in the industry is convinced of the benefits of screwcaps.  Finally and most importantly, the customer. Cork taint is not an issue that is widely understood and many wineries are afraid their customers will not accept screwcaps.  Research suggests that consumers overwhelmingly prefer cork to any other type of closure, mainly because they associate screwcaps with wines for “winos”.

corkHowever the Kiwis don’t have time for such niceties, they have simply said “Sod the research, the customer needs this improvement”. Thery have been so successful that the screwcap is the closure of choice for the UK supermarkets, who like the cost reductions and the lack of problems with “corked bottles”. It also helps that the quality of New Zealand wines is alost universally high, regardless of the price point. The rest of the world is rapidly following New Zealand’s lead.    

So, if the Kiwis see the economic sense in screwcaps, why are the top Chateaux of Bordeaux not switching?” When asked this question, many top producers will rightly answer that they continue to respond to customer expectation – there is more to a bottle of wine than the liquid that is in the bottle, particularly at the top end – it is more of a “luxury” product and should have “luxury packaging”.  However, many are or are at least beginning to experiment, Guy Laroche  in Burgundy and Chateau La Louviere in Bordeaux have already taken such steps and one of the biggest of them all, Chateau Margaux now has screwcaps on its “Pavillon” label.

So, screwcaps on wine bottles are the coming thing, but  not in a huge rush in traditional minds. To quote one of my winemaking chums at a top estate in South Africa, “Yeah sure, we lose one or two bottles to the old buggers (corks), but cracking open a screwcap ain’t anything like pulling a cork!”

Does this raise questions or comments, then e-mail Stephen and he'll be only to glad to answer and expand on anything you want to know more about             


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