What’s the twist
on screw caps?
Going corkless is gaining
By Annette Alvarez-Peters
approval among winemakers
DURING A VISIT to Australia last year, I and stacked outdoors for at least six months.
marveled at the spectacular view atop the hill- The strips are then boiled to kill any mold or
side vineyards at Jacob’s Creek winery. As we bacteria and to increase the cork’s elasticity.
sampled the 2002 Steingarten Vineyards They’re then punched out to form a cork, dis-Riesling, a wine bursting with honeysuckle, infected in a chlorine or hydrogen peroxide
with an essence of white floral and fusel notes bath, graded, branded and sealed for ship-
(typical in aged Riesling), I noticed some- ment to wineries.
thing unusual: This fine wine had a screw But as wine production throughout the
cap—and had indeed aged world has increased, so has the
gracefully without the help of demand for cork, straining the
acork. supply of quality material.
It’s something that we’ll Inferior corks can cause a vari-see more of—and that’s not ety of problems and are prone
bad. Screw caps are one of to the contamination that can
several alternatives to the tra- spoil a good bottle of wine.
ditional natural cork closures The culprit behind the confor bottled wines. For many tamination is trichloranisole
wines, screw caps work per- ( TCA), a chemical byproduct of
fectly well. They eliminate the chlorine disinfecting pro-the possibility of “corked” cess. Large-scale TCA contami-bottles—those spoiled by nation renders a wine musty
a contaminated cork. And or moldy, with strong odors of
they ease demand on quality Annette Alvarez-Peters wet cardboard. Slightly corked
cork supplies. wines suffer muted flavors and
The winemaker at Jacob’s Creek provided are generally lifeless. TCA is not harmful to
a lesson on the topic. A widely used version of humans, but it is lethal to wine.
the screw cap is the Stelvin capsule, designed Statistics show that fewer wines are
specifically for contact with the wine while in corked these days—about 5 percent of all
the bottle. The oxygen in the bottle, along with production, down from 10 percent, thanks to
the small volume of air in the head space, or new alternatives to using chlorine. Still, this is
ullage (the area between the cap and the a big problem by any measure and con-wine), results in a slow, limited aging process. tributes to the argument against corks.
Leading winemakers are using screw
caps as an alternative to corks.
if you bring a vibrant bottle of Sauvignon
Blanc with a screw cap to a garden party?
For my money and experience, I trust the
screw cap. I can cellar wines safely, the bottles
are easy to open and I never have to worry
about the ultimate wine letdown: a corked
bottle of a favorite varietal. I think we can all
trade a little romance for the security and
pleasure of drinking unspoiled wine. Go
ahead. Experiment and enjoy! C
A departure from tradition
This is, of course, a radical departure
from tradition. Wine lovers have savored the
“pop” of uncorking wine for more than 400
years. Natural cork has been the most popular wine bottle closure and still is today.
Wine corks come from the bark of cork
trees, a member of the oak family, grown predominantly in Portugal and Spain. The bark
is stripped from the trunks and large branches
For information on Costco’s
Kirkland Signature™ wines,
including vintage notes and food-pairing
tips, go to costco.com, click on “Costco
Connection Magazine,” then “Kirkland
Signature Wine Connection.”
To cork or not to cork
Annette Alvarez-Peters oversees Costco’s
national wine, spirits and beer program.
Despite these benefits, questions linger
about screw caps. Winemakers around the
world are debating whether going corkless is
right for their wines and their businesses. For
about 10 percent of the world’s top wines,
aging is a crucial concern: Natural cork is
somewhat porous and allows necessary airflow
to allow these wines to develop to their full
potential. It’s debatable whether these wines
can age properly with screw caps. Clearly more
trials and experimentation are needed.
Image is another major consideration.
Are wine consumers ready for screw caps,
which for many years in the United States
have been associated with cheap, low-quality
wines? Will there be a tide of rising eyebrows
Corkless at Costco*
Amisfield Pinot Noir
Conundrum White Blend
*Not all wines available at all locations.
See costco.com for more wine choices.