"This is something to get excited about," said prominent oenologist Michel Rolland at the annual futures tasting. "It's a great vintage with precise wines, better than any we've ever made," he said. "It has the power of the 2005s and... the body and sunny charm of the 2009s."

South African Neil Pendock, who owns a wine shop in Cape Town, agreed. "I've been coming for the primeur tastings for about four, five years now and this is the best," he said, praising the wine's accessibility and fruitiness. He predicted a big success for the vintage.

Wine expert Stephan Toutoundji of tasting laboratory Oenoteam in nearby Libourne in southwest France said the exceptional quality was true across all the Bordeaux labels for 2015, "on a par with the last great ones -- 2005, 2009 and 2010".

Wine futures are sold to buyers on exclusive contracts who then resell their selections to clients who will not receive their wine until it goes on the market in 18 months. The system is used by only 150 Bordeaux wineries representing around two per cent of production.

The opinions of the expert tasters attending the annual week-long event are crucial to future sales and help determine the prices that will be set at the end of May.