The Grapevine: Tablas Creek winemakers weigh the value of corks vs. screw tops

By Laurie Daniel

Although some wineries, especially in New Zealand and Australia, have embraced screw caps for all or nearly all of their wines, most are moving more cautiously. In some cases, they’re testing the twist-off closures on a few cases of a particular wine and assessing the results before moving ahead.

Tablas Creek Vineyard in Paso Robles is one winery that has been performing such tests, starting with the 2002 vintage. The results led the winery to decide to bottle certain wines—the rosé, most of the whites and the counoise, for example — with screw caps.

The winery staff periodically tastes and compares the screw-capped wines against the cork-finished examples, and a couple of months ago I sat in. Winery General Manager Jason Haas poured a selection of such wines for me, managing partner Robert Haas (Jason’s father), and winemaker Neil Collins. The tasting was blind—that is, we didn’t know which wine was which.

Matching wine and cap

The Tablas Creek team has tried to match each wine to the proper closure. Jason Haas blogged on the subject last summer on the Tablas Creek Web site. “We do our best to match up the wine with the closure that best allows it to age and evolve gracefully,” he wrote, “and the answer is not the same for all wines, any more than a one-size-fits-all prescription for wine-making would be.”

He added that, in the winery’s experiments, “wines bottled under screw caps taste fresher, higher in acid, younger, tighter, and more mineral. Wines bottled under cork taste softer, sweeter, richer, more open, and more evolved.

“Which is better is not a simple question, and it depends on what we want out of the wine,” Haas said. “For an aromatic white, or for our rosé, we like the brightness and freshness that the screw cap provides, and feel that the screw cap will have the additional benefit of keeping these wines (which are typically meant to be enjoyed young) tasting youthful longer. But those same characteristics do not benefit most of our reds, and they do not benefit our roussanne-based whites, all of which we want to develop that softness and sweetness that time brings to wines meant to age.”

In our discussions, Haas elaborated. Some grapes that Tablas Creek works with, such as roussanne, mourvedre and syrah, are more susceptible to reduction. Wines that are reduced develop sulfur compounds that can impart off-aromas and flavors like rotten eggs, onions and rubber.

The main point of controversy surrounding screw caps these days is whether they contribute to a reductive character in certain wines. Tablas Creek has, for the most part, avoided screw caps on wines that are more likely to become reduced.

Benefits of a cap

Still, the benefits of screw caps were evident to me in the comparative tasting, no matter what grapes were involved.

We started with the 2003 vermentino, 2003 rosé and a 2002 blend of syrah, mourvedre and grenache known as Las Tablas Estates (the winery no longer produces it). Although the vermentino and the rosé, which should be drunk young, were a bit tired, in each case the screw-capped wine was fresher, with more vivid fruit. The Las Tablas Estates wine under screw cap was peppery and bright, with juicy fruit, while the version with a cork was much tighter and not nearly as expressive. No problem was evident, despite the syrah and mourvedre.

Because the rosé contains a high percentage of mourvedre, “that’s the one that makes me most nervous,” Collins said. No problem there, either.

Last year, the winery tried this test on the 2005 Côtes de Tablas ($22), a blend of mostly grenache and mourvedre, along with some syrah and counoise. A couple hundred cases were bottled with screw caps for sale in the tasting room. Although both the screw-capped and the cork-finished wines were still quite tight, the bottle with the screw cap displayed more sweet fruit, while the wine with a cork showed a lot of tannin.

“I don’t see anything here that would argue leaving them in cork,” Jason Haas said. His father agreed. “I’m most tempted to move into screw cap with the Côtes red,” Robert Haas said.

I checked back recently with Jason Haas, and he said that 300 to 400 cases of the 2006 Côtes de Tablas will be bottled under screw cap for further comparison. “It seems like something we want to take a look at,” he said.

Laurie Daniel writes a weekly column on wine. E-mail her at ladaniel@earthlink.net.