Gallo Confirms Tainted Wine

Wines bottled at E. & J. Gallo Winery’s processing facility in Sonoma have been tainted with TCA, a pesky chemical that produces a musty aroma and cardboard-like taste.

Gallo confirmed the contamination, which was first reported in the Wine Spectator after a critic for the influential magazine detected “chalky” and “bitter” flavors in Gallo wines and sent the vintages he tasted to an independent laboratory for analysis.

Mary Wagner, chief technology officer for Modesto-based Gallo, said Wednesday that the contamination occurred in trace amounts. TCA poses no health hazards.

“We don’t believe it is a consumer issue, and we are not recalling any wine,” Wagner said.

Wagner said she didn’t expect news of the contamination to hurt sales.

Jon Fredrikson, who heads Gomberg Fredrikson Associates, a wine industry consulting firm, said Wagner might be right.

“This is something for the super-critics to be concerned about rather than the average wine drinker,” Fredrikson said.

Gallo, the world’s second-largest wine company, is the second big California winery to suffer an outbreak of TCA contamination in recent years. Beaulieu Vineyards in Napa Valley spotted TCA in a number of its red wines last fall and traced the problem to a humidifier in one of its cellars.

Beaulieu’s shipments declined in the months after the contamination, as merchants canceled orders, fearing they wouldn’t be able to move the product -- even though some retailers didn’t personally find anything wrong with the affected Beaulieu vintages.

“I tasted the BV wine and I thought it was overblown,” said Randy Kemner of the Wine Country in Long Beach, which halted orders.

Earlier this year, Hanzell Vineyards, a small Sonoma winery, spent about $500,000 investigating a TCA outbreak and replacing equipment to control it.

TCA is the abbreviation for trichloroanisole, a chemical byproduct of the interaction between mold and chlorine, which is used as a cleaning solution and to bleach corks and oak barrels. Contaminated corks are often a source of TCA in bottled wine.

“It is the mold’s trick for getting rid of chlorine,” said Linda Bisson, a microbiologist and professor of enology at UC Davis.

TCA, she added, “is a nasty character.”

Some people are sensitive to TCA’s unpleasant odor in concentrations as small as 1 part per trillion, Bisson said. But there is no firm threshold at which most imbibers begin to detect the TCA taint in their wine. Bisson noticed that her college students generally begin to smell or taste TCA at concentrations of 2 to 5 parts per trillion.

Jean Arnold, president of Hanzell Vineyards, said research done after her winery discovered contaminated wine found few consumers who could notice TCA at less than 4 parts per trillion.

Because discerning the chemical’s presence varies greatly by individual and by type of wine, the Wine Institute has not set a standard for TCA contamination, said Gladys Horiuchi, spokeswoman for California’s largest wine trade organization.

“And because it is not a health risk, no government agencies in any part of the world have sought to regulate TCA levels in wine,” Horiuchi said.

Gallo said its tests showed an average contamination of 1.9 parts per trillion in the wine coming out of its Sonoma winery. Located in Dry Creek Valley, the complex produces 90 different Gallo wines totaling nearly 2 million cases a year under such labels as Rancho Zabaco, Frei Brothers, Gallo of Sonoma and Louis Martini.

“We are finding that it is really random,” Wagner said. “You can look in one barrel and see it, and then it won’t be in the next. We are doing everything we can to understand it. “

One sampling found a bottle of Gallo’s 2000 Louis Martini Napa Valley Cabernet Sauvignon with a reading of 5.6 parts per trillion, and another found a 2.5 result in a 1999 Gallo of Sonoma Frei Ranch Vineyard Cabernet. Wagner said she believed those elevated readings resulted from problems with corks rather than contamination within the winery’s cellar.

Privately held Gallo controls a third of the state’s wine production and has estimated annual sales of about $1.7 billion. The Sonoma facility accounts for a small percentage of the 66 million cases of wine Gallo ships each year, but it processes many of the company’s more expensive wines.

The Wine Spectator reported that it first detected hints of TCA in blind tastings of Gallo wines as far back as a year ago, and “since then, 35 of 75 Gallo-made wines that were tasted displayed off flavors consistent with TCA.,” the magazine said on its Web site.

Bisson said wineries had to take great care in using chlorine and bleach as cleaning solutions in their operations. Many wineries are shifting to citric acid or hydrogen peroxide. One of the mysteries of the Gallo contamination is that the winery stopped using chlorine as a cleaning agent years ago, Wagner said.

The wine industry has known about TCA for several decades; most cases have been traced to the bleaching of corks to get the light tan color that consumers expect when they peel the foil from the bottle top.