Screwcaps have failed in France

Before Facebook, it took time for one revolution to inspire another. Take screwcaps. Invented in 1889 in Barnsley, they didn't infiltrate the wine world for another 111 years.

When they did, the Tahrir Square of the uprising was Clare Valley, Australia. Then, in 2001, New Zealand fell. Screwcappers found a receptive audience for their air-tight, anti-cork rhetoric among quality-minded and cost-conscious New World winemakers (though rarely among wine lovers).

Their calls for "Freedom of Closure" saw corks pushed from office like out-of-touch, end-of-life dictators.

Screwcaps promised to rid the world of trichloroanisole (TCA), the chemical in tainted corks making wine smell mouldy, or "corked". Early-adopters claimed the closure was incorruptible and represented the most important advancement in wine quality and consistency in the modern era.

Wine traditionalists and cork industry stakeholders feared a domino effect. Yet today, screwcaps aren't widely accepted as the closure they purported to be and they're on the banned list across many French terroirs. Not because tradition blinds Old World winemakers to science. And not jealousy: the world's leading screwcap manufacturer is a French firm.

Screwcap PR simply spurred the cork industry to clean up its act. Cork "failure" is now just two to five per cent (i.e. better than typical condom use). During the old regime's worst abuses, "failure" was eight to 10 per cent. It was precisely TCA's rarity that made spotting a corked wine the aficionado's party trick.

And screwcap science unwound. Wines incubated just 12-18 months under screwcaps' near-anaerobic conditions too often came out stillborn, smelling of rotten eggs. Whereas cork lets wine breathe and mature, wines asphyxiated by a screwcap can suffocate on their sulphides and don't age gracefully.

Still, a recent screwcap PR photo purports to show white wine sealed 10 years ago under screwcap looking as bright as the day it was bottled. The same wine sealed under cork looks jaundiced. This is supposed to prove that wine can age under screwcaps.

Wine critics describe "the screwcap palate" as bitter, coarse and astringent, with blunt fruit and an abrupt, harshly dry finish.

Spotting a screwcapped wine is their new party trick. Screwcaps' advocates recommend "cleaning" wine to be sealed under screwcap with copper sulphate repeatedly during vinification. This supposedly lowers the level of sulphides that the screwcap traps in the bottle. However, copper "fining" can seriously undermine varietal character and residues can reach undesirable levels.

So, a decade on, is the screwcap revolution over? I asked a Roussillon winemaker for whom adopting the screwcap would be a patriotic act: Barnsley-born, New Zealande-respoused Jonathan Hesford (www.domainetreloar.com).

He reckons just two per cent of the corks he now buys show taint, compared with 10 per cent a few years ago (his suppliers claim to have significantly reduced or eliminated TCA). And he is sticking with corks because of worries that tannins and fruit don't evolve harmoniously under screwcaps' very low oxygen ingress.

"Screwcaps are not really for wines made to age in a bottle," he concludes.

Yet "breathable" screwcaps do exist. They're the industry's equivalent of Reliant Robin's engineers deciding four wheels, after all, is the way to go. Perhaps there are some among the one-in-10 screwcapped wine bottles at my local supermarket.

But how can you tell? And where's the evidence they work? I'm happy Hesford is on the "unpatriotic" side of the screwcap curve. Wine quality aside, he's on the right side of 60 million years of Mediterranean ecology: one of France's cork-oak forests (the Massif des Alberès) is in the Pyrénées-Orientales, where he lives; others are in the Var (the Massif des Maures), the Landes and Corsica. They are habitats for rare tortoises, owls, spotted genets and cork farmers.