NEW YORK: Looking for a good bottle of Merlot, Pinot Grigio or Bordeaux? Ratings by experts may help narrow the choice, but do they really make a difference?

Wine experts say the scores and descriptions they give a vintage will differentiate a good bottle from a mediocre one but in a recent study consumers who tasted fine Bordeaux rated the wines lower than the experts.

“The consumer can look at it [the rating] and say, ‘OK a panel of experts has looked at this wine and evaluated it and I know it won’t be plonk,’” said Lisa Granik, who holds a Master of Wine, one of the highest standards of expertise in the wine industry.

Wine experts, magazines and judges in competitions give wine ratings, which are used as marketing tools by the vineyards. Competitions charge a fee for each product entered in the contest.

Granik, along with five other MWs and other wine experts, spent three days last week tasting and rating 700 wines for the Ultimate Wine Challenge, which gives ratings for wines that make the grade ranging from good/recommended to extraordinary/ultimate.

Doug Frost, another MW who took part in the challenge, believes ratings offer reassurance to consumers about the quality of the product.

“If not a third party endorsement then [if offers] at least some measure of security that at least some people have tasted this and at some point in the past have found it delicious,” he explained.

But Ed McCarthy, another judge and the author of “Champagne for Dummies,” said many good wines never enter competitions and don’t get rated.

“There are those that don’t have the money and there are those who don’t need it and don’t want it,” he explained. “A small winery isn’t going to enter these things because they don’t make enough wine. And if you sell all your wine, you don’t need to.”

The Ultimate Wine Challenge charges wineries $95 for each product entered and ranks wines ranging in price from $6 to $235 a bottle.

For Jennifer Simonetti-Bryan, another judge who has a MW, context is important.

“If you are tasting midmarket Chardonnay, is it an excellent quality one, or is it of poor quality?” she said.

But Omer Gokcekus, a professor of international economics at Seton Hall University in New Jersey, has doubts about the value of ratings.

In a study in which he asked consumers to rate fine Bordeaux he found that they generally gave the wines lower ratings than they received from U.S. wine critic Robert Parker or Wine Spectator magazine.

“Given MWs’ comprehensive knowledge, a bottle of wine rated by the MWs is, undoubtedly, not going to be plonk. However, that doesn’t necessarily mean that regular wine drinkers will like it as much as the MWs do,” Gokcekus said.

“There is even a possibility that they won’t like it at all.”