Rotten corks ruin 40 million bottles a year, tasters claim

Up to 40 million bottles of wine drunk in Britain each year are ruined by the musty smell of cork taint, the largest survey of wine quality has discovered.

The finding confirms the suspicion long held by Britain's best-known wine experts, restaurateurs and food critics that an unacceptably high proportion of wine is being spoiled by poor-quality corks letting in mould.

It will also lend strength to a solution gathering widespread support in the food and drink industry – aluminium and plastic screwcaps.

A growing number of experts, including restaurateurs such as Gordon Ramsay and Antony Worrall-Thompson, and wine producers in New Zealand, Australia and California, argue that screwtops are fault-free and preserve the taste and quality of young wines far better than corks.

Only the most prestigious wines made for laying down, such as Clarets, Burgundys or Sauternes, deserve a cork.

Tesco thinks its customers agree. Over the past 12 weeks it has sold more than 1.5 million bottles in a range of 28 screwtop wines, including from the makers Lindemans, Penfolds and Hardys. Mr Worrall-Thompson, meanwhile, sells six screwtop wines at his Notting Grill restaurant in west London. The idea that screwtops are "common" is now old-fashioned, he says. "It's a deep perception – it hasn't got a cork, so it must be crap. But that just isn't true now."

The Wine and Spirit Association presents the survey this week, after taste tests of more than 13,000 wines. The survey was provoked by a wine trade row about the extent of the "taint problem" – caused by the fungus known as 2-4-6 trichloroanisole, arising from dirty or ill-fitting corks, which gives wine a whiff of mushrooms and often an unpleasant taste.

Up to 10 per cent of bottles can be tainted, observers say. The WSA gives a latitude for "faulty wine" at 1-3 per cent of the 1.2 billion bottles sold each year. Its director, Quentin Rappoport, says improved cork quality or plastic corks or screwcaps will follow. "The implications are very strong for the cork industry."

Even so, the size of the problem may be underestimated. Chris Losh, editor of the magazine Wine, said that a recent staff tasting had turned up 12 corked wines in 150 samples.

But controversy still reigns over the use of screwtops. Mr Ramsay's London restaurants sell a screwtop Riesling, but Aaron Paton, the sommelier at the chef's Amaryllis restaurant in Glasgow, will not stock it, claiming people "don't want their wine in a lemonade bottle". However, Mr Ramsay's chief sommelier, Ronan Sayburn, says: "There are impassioned people who believe there's something cheap and nasty about a screwtop. But there's a huge amount of corked wine, so a screwtop is the most logical thing."