Columnist, Food

To understand the impact of climate on wine, look to sauvignon blanc. The weather affects other varieties, of course, but sauvignon blanc, a.k.a. sauv blanc or even savvy among its closest friends, is illustrative because the consequence of temperature is so easy to taste.

Sauvignon blanc’s homeland is the Loire Valley of France, where it reaches its supreme expression in the mineral wines of Sancerre and Pouilly Fume. The Loire is considered a cool-climate wine region. You won’t find rich, fleshy chardonnay there, and full-bodied reds of cabernet sauvignon and syrah are virtually unheard of. A good Sancerre, such as the Henry Natter 2010 ($29), tastes of red currants and a tinge of smoke. There is also a slight, yet noticeable, green quality: a grassy herbal flavor that is sauvignon blanc’s signature.

Transplant the vine to an even cooler region, such as New Zealand, and the grassiness becomes more pronounced. New Zealand savvy became a worldwide rage in the 1990s as consumers grooved to the wine’s pungent herbal qualities and racy acidity. Sauvignon blanc became a darling of the “anything but chardonnay” crowd tired of oaky, buttery flavors in their white wine.

That recognizable New Zealand character was a product of the country’s climate and the grape’s natural vigor; by allowing the vine’s canopy to sprawl and shade the grapes, vintners accentuated aggressive, herbal flavors. New Zealand sauvignon blanc was said to smell of “cat’s pee on a gooseberry bush.” And that was considered good, even by dog lovers. Those who didn’t care for the flavor likened it to that of stewed asparagus.

More recently, New Zealand vintners have worked to tame the vine’s vigor and control that grassy character. Mostly, that means trimming leaves to expose the grapes to more sunlight. The result is a more elegant, restrained sauvignon blanc that retains its New Zealand signature while allowing the grape’s fruit to shine.

Seifried winery demonstrates that contrast with two wines. The Old Coach Road 2012 sauvignon blanc “is a more recognizable New Zealand” expression, said Anna Seifried on a recent visit to Washington. “With the Seifried blend” — the family’s main label — “we wanted a more classic expression of the grape.” Both wines are delicious, with the Seifried offering greater elegance and subtlety. At $15 and $19, respectively, both are great values.

California shows what sauvignon blanc can do in a warmer climate, but its track record has not always been great. Not too long ago, wineries there were boasting that they’d gotten rid of the grassy herbals by picking the grapes ripe, then aging them in oak barrels. That approach tended to strip the wines of any varietal character and made them taste like weak chardonnay.

Napa Valley sauvignon blancs, such as the ones made by Frog’s Leap, Grgich Hills and Robert Mondavi, can be ripe and tropical, fruitier than Sancerre’s and less green than New Zealand’s. A more classical style is apparent in Sonoma County, and the best sauvignon blanc is produced by Matanzas Creek Winery and Dry Creek Vineyards.

“What sets Sonoma County sauvignon blanc apart is the interplay between coastal fog and volcanic soils,” Matanzas Creek winemaker Marcia Monahan explained in an e-mail. The fog moderates Northern California’s heat, while the soils lend structure and length to the wines. 

Monahan blends wines from three areas of Sonoma County into the winery’s popular main bottling, and she has just launched two single-vineyard sauvignon blancs: from Bennett Valley, near the town of Sonoma, and from Knights Valley, farther north near Mount Saint Helena. Bennett Valley’s cooler climate gives the wine natural acidity and flavors of guava and litchi, she said, while greater sun exposure at the Helena Bench vineyard in Knights Valley lends flavors of passion fruit and peaches.

With an expressive grape like sauvignon blanc, even minor climatic differences within a region can transform a wine.

McIntyre blogs at Follow him on Twitter: @dmwine.