As many as a third of the vineyards in Bordeaux could be up for sale, according to a leading negociant.

Yvon Mau's managing director Philippe Lequeche claims that the economic downturn is affecting profitability at many unclassified estates, resulting in a generational divide.

As existing owners are approaching their retirement, the next generation are less keen to take on struggling businesses and estates are forced onto the market, Mr Leuqeche told the Drinks Business.

However, this may not necessarily be bad news for Bordeaux, the negociant explains, adding that many of the struggling estates are on the poorer terroirs.

"My feeling is that we have too many hectares in Bordeaux for quality and demand," he told the publication.

The director of Bordeaux property agent Vineyard Intelligence, Alex Hall, suggests there may be some truth in Mr Lequeche's claims, saying: "There are 8,200 producers in Bordeaux – are one third of them on the market? I'm not sure.

"But in terms of people who, if they thought they could sell, would – yes, probably."

After a flurry of recent deals in Bordeaux, it is estimated that close to 20 estates in the region are now or could soon be in the hands of Chinese nationals.

Mr Hall says that this is one positive aspect of so many estate owners looking to sell, as with new ownership comes fresh ideas and alternative distribution channels.

"New owners are bringing in new markets. These guys are buying what other people wouldn't be keen on buying. It's difficult to make money at a certain economy of scale because of distribution," he told the Drinks Business.

One of the recent sales saw Chinese film star Zhao Wei take possession of the Chateau Monlot estate in St Emilion, while Chateau Lezongars and Chateau Grand Branet in the Entre-Deux-Mers region have also been bought by Chinese nationals.