Wine personality of the decade? The screwcap

As the recent online survey on the excellent Dr Vino blog has demonstrated rather well (IMHO), it’s very hard to pick one single person who deserves to win this award. So my vote goes to a thing, not a person. And that thing is the screwcap.

10 years ago cork was performing pretty badly. Cork taint was a big issue, and the Australians were also getting cross about a phenomenon called random oxidation, caused by the variable nature of oxygen transmission by poor quality corks.

The only alternative to cork was the new but rather poorly performing plastic cork, and that wasn’t winning too many friends. So cork producers had little motivation to up their game, because they enjoyed what was effectively a monopoly situation.

The major breakthrough came in 2000, when a bunch of Clare Valley producers formed a coalition to release their Rieslings under screwcap. This initiative, and the publicity that ensued, changed the closures market forever.

As the results from the Australian Wine Research Institute’s Closures Trial, initiated in 1999, began to appear, they showed that screwcaps kept the wine fresher and fruitier for longer than any of the other closures available, including natural cork.

The adoption of screwcaps by the Australian and New Zealand producers was almost immediate. With the tin/saranex liner, screwcaps now seal the vast majority of bottles in these two countries. Of the estimated 18 billion bottles of wines sealed each year, screwcaps now account for over 2 billion (synthetic corks have also done well, and account for around 4 billion).

But screwcaps aren’t the perfect closure. Currently there are just two liners used: tin/saranex and saranex only. The first, the one used almost exclusively in Australia and New Zealand, allows very little oxygen transmission at all (probably not enough), and the second a little more than an average natural cork: ideally, we’d like a liner with intermediate properties.

And they haven’t been widely accepted in all markets. But what they have done is change the closures market completely. Were it not for screwcaps, it’s unlikely the cork industry would have implemented the quality control measures that they have. And it is unlikely that we’d have seen the rise of alternative closures such as Diam, Vino-Lok and the improved new generation synthetic corks. It is only since they've been widely used that we've started to get to grips with post-bottling wine chemistry.

The noughties have definitely been the decade of the screwcap.