But in a scandal being dubbed 'Winegate', the 2006 vintage has been stripped of its medals, and chief winemaker Brent Marris forced to resign as head judge of the country's most prestigious awards. Marris's departure was prompted by an inquiry which established that the Wither Hills Sauvignon Blanc entered in competitions was different from the one being sold to the public.

Marris blames a technical error, and has hit back at rival winemakers who he claims are jealous of his success. It was their murmurings that prompted Michael Cooper, chief judge of Cuisine magazine, to blind-test the wine that won gold in the magazine's awards this year against one bought in a supermarket. Cooper concluded they were "two different wines"; scientists at a government lab confirmed different levels of sugar, alcohol and acidity.

Marris explained that bottles from an early batch . . . made separately to "best represent" the vintage . . . had mistakenly been sent for judging. But the judges were not impressed.

There are fears the scandal may affect an industry worth NZ$1bn a year. Wither Hills had become New Zealand's best-selling Sauvignon Blanc, with over a million bottles produced a year.