The influence of the movie "Sideways" (search) has some wine drinkers' favorite tipple turning to vinegar in their mouths.

Though the vino-drenched comedy has inspired more people than ever to flock to their local cafes, wine shops and vineyards to sip a glass of red or white, it also has put a cork in sales of Merlot (search), until now one of the most consistently popular varietals of red wine among Americans.

"Right now Merlot is definitely in the doghouse when it comes to desired varietals — a victim of the 'Sideways' effect," said Mark Oldman, author of "Oldman's Guide to Outsmarting Wine."

In the film, failed writer and lovably cranky oenophile Miles Raymond (Paul Giamatti (search)) and his best friend, affable minor actor Jack (Thomas Haden Church (search)), take a tour through California wine country before Jack's impending wedding.

Miles has one major pet peeve when it comes to wine: Merlot, which he generally despises as a common but mediocre product of the sacred grape. He vastly prefers Pinot Noir (search), the grape of which is harder to grow but which some find immeasurably more rewarding.

The contrast between Merlot and Pinot Noir can be seen as a mere metaphor for the differences between gregarious but shallow Jack and prickly but soulful Miles, but thousands of moviegoers have apparently taken Miles' advice to heart and are snubbing Merlot.

At the Wine List wine shop on the main drag in Hyannis, Mass., co-owner Jackie Kantrowitz and her sister have been serving wine to Cape Codders for over two years. But now those glasses are definitely being filled with less Merlot, she says.

Before the movie came out, the shop bought about 15 cases of Merlot every week. Nowadays, they're putting in orders for only 12 or 13.

"More than ever since the movie's gotten so many awards and so much publicity, I'm noticing that there's a drop in sales in Merlot," Kantrowitz said. "I would say Merlot may be down 10, 20 percent. I don't know if it's the Oscars (search), but it's especially in the last couple weeks."

On Sunday night, "Sideways" won the Oscar for best adapted screenplay.

Even amateur oenologists have changed their ways.

"I went out for a Pinot Noir after I saw the movie, and I've not had a Merlot since," said 33-year-old New York art director Zoe Chan.

Merlot's downfall has been long overdue, according to James Laube, senior editor at Wine Spectator (search) magazine. Not long back, the wine enjoyed a sudden popularity as increasingly sophisticated American consumers thirsted for more than Cabernets or red table wine.

But unscrupulous winemakers overestimated its demand, and for the past 10 or 15 years have produced it in record numbers, flooding the market with inexpensive merlots of dubious quality.

"I don't know whether Paul Giamatti has single-handedly put an end to Merlot, but it was due for a correction," Laube said. "His [character's] shot at Merlot obviously doesn't help — although, of course, there's a weird irony in that his favorite wine is Cheval Blanc, from St. Emilion, which is a blend of Cabernet Franc and Merlot. I think it's intended to show that wine snobs, though they talk a good game, don't know what they're talking about."

There's little sympathy for Merlot-heavy vineyards from Chris Shipley, wine director for the famed 21 Club (search) in New York City.

"California destroyed its own Merlot business a number of years before the movie was even released," he said. "Customers have come to realize that the ones the growers were devising to fill this supposedly endless demand for the grape weren't very good. And so there's a fatigue on the customer's part. The craze is clearly over, and the movie was picking up on that."

If there is a silver lining for vintners, it's that "Sideways" has also seemed to spark heated interest in Pinot Noir — something Miles would certainly be ambivalent about.

Kantrowitz said sales of pinot at her little shop have rocketed by 30 or 40 percent — she has to order some 20 cases a week. And Laube points out that beginning pinot drinkers have the great fortune to discover the wine at maybe the best moment in history.

"The 2002 vintage was the best vintage in California history up and down the coast, so you have every reason in the world to pursue Pinot Noir," Laube said. "The timing couldn't be better."

He noted, however, that because there were fewer pinots than merlots being made to begin with, even a relatively small increase in pinot sales may look big on paper.

Still, there are a lot of other factors pushing for pinots, experts said. Aspen, Colo., oenologist Stephen Reiss, author of "Juice Jargon: How to Talk About Wine," said tart pinots make an ideal companion to food. And it's long been preferred among connoisseurs.

But Merlot lovers needn't despair.

"Merlot will likely regain much of its popularity, because it is such a likeable wine — soft, rich, without the gum-numbing bitterness that wines like Cabernet Sauvignon (search) can have," Oldman said. "Also, and this may seem trivial but it's not, it is really easy to pronounce, which makes a difference in what people order."

And Pinot Noir should take a lesson from what befell its disgraced brother, Shipley said.

"Undoubtedly what's going to happen is all these California wineries will say Pinot Noir's really big and then make a whole bunch of crappy ones, and the customers will turn their noses up at all Pinot Noirs, and we'll have a cyclical thing like we did with Merlot," he said.