It is the harvest of the century in Bordeaux, with exceptional weather conditions producing grapes so fine that dogs are turning vegetarian to eat them.

That, at least, is what the region’s wine-makers would have you believe as they lavish praise on this year’s pickings. But the claims have prompted wry smiles from French critics and drinkers, who recall that Bordeaux’s châteaux said much the same thing about the 2005 vintage — as they did about 2003 and 2000.

“It’s yet another vintage of the century,” said Bernard Burtschy, a respected critic, in Le Figaro newspaper. “In the face of a depressed market, producers are trying too hard.”

Sceptics say that after a 45 per cent fall in prices last year, wine-makers are talking up their harvest to bolster revenue when it is sold to merchants next year.

Gil Lempert-Schwarz, chairman of the Wine Institute of Las Vegas, said that the hype was “mainly a ploy” to offset falling sales amid the economic crisis.

This year, the claims began even before the merlot and cabernet sauvignon grapes had been picked, as owners highlighted ideal weather in September — 233.49 hours of sunshine and 48.6mm of rainfall.

“You have to go back to the weather reports of the Forties to find, perhaps, comparable conditions,” said Denis Dubourdieu, director of the Institute of Vine and Wine Sciences in Bordeaux, who is also a producer.

“It is an explosion of fruits and flowers,” said Alain Moueix, the owner of Château Fonroque at St Emilion, after tasting his grapes. “It’s unctuous, suave, totally unusual. It’s like love at first sight. You can hardly believe it.”

Hubert de Boüard, owner of Château Angélus, also at St Emilion, said: “I have a young labrador. It is the first time I have seen him sink his teeth into a bunch of merlot grapes.”

Connoisseurs said that there was some truth in the claim that 2009 might prove memorable — but Bordeaux’s châteaux had oversold harvests so often that they had drained public confidence.

“There’s no denying that they hype it every year,” Anthony Maxwell, a broker at Liv-Ex, London’s fine wine exchange, said. “This year it is more frenetic than ever but there does seem to be some justification. The quality of the grapes is certainly very good.”

However, critics say that it is far too early to start drawing conclusions about the 2009 vintage, which will not be tasted by critics until April, purchased by merchants until June and not be consumed at dinner parties for at least five years.

How to make a corker

• A good vintage requires benign weather - sun, not too much heat, enough rain and gentle wind

• A severe winter kills off harmful bugs and allows the vines to rest. A wet spring replenishes the water table, increasing the yield. Fine dry summers are helpful but too much heat can turn grapes into raisins

• Previous much-lauded vintages in France include 2000, 1995, 1982, 1961 and 1945; 2005 was fêted as one of the best for decades. In a good year, picking can begin weeks earlier than usual because grapes have ripened quickly, putting them less at risk

• Good vintages produce balanced, concentrated wines that are appealing when young but also mature well. This makes them valuable to investors

• In October last year the price of vintage wines fell by 25 per cent. A case of 2000 vintage from Château Ausone — ranked Premier Grand Cru Classé — fell from £15,575 to £12,200

Source: Times database

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