IT has built its reputation on beer.

Now the duo behind Brewdog, the fast-rising Aberdeenshire brewer and pub group, is aiming to cause a stir in spirits.

WattDickie, a beer-based spirit created by a secret brewing and ice distillation process, made its first public appearance at Brewdog's Underdog bar in Shoreditch, London, yesterday.

The first non-beer product to be made by the brewer, the 35% alcohol by volume (ABV) spirit is sold in 6cl bottles priced £2.99, and can be consumed straight or in a range of cocktails.

Named after the company's founders, James Watt and Martin Dickie, it will be available in Brewdog's 12 bars and online from the end of the month, with Brewdog also planning to make it available in 700ml bottles later in the year.

Precise details of its production method are being held secret until the patent is secured for the process.

However, the company has disclosed that it was created using an IPA-style (India Pale Ale) beer.

A spokeswoman said the distillation technique had been "built from scratch", and stemmed from the brewer's experience in creating the limited edition, high ABV beers Tactical Nuclear Penguin, The End of History (served in taxidermy-style bottles made from dead squirrels) and Sink the Bismarck.

WattDickie, which features soldiers with shark and fox heads on the labelling, will be marketed as a brand in its own right. At this stage there are no plans to turn it into a range of products, however the spokeswoman added that "you never know" if the position may change.

James Watt delivered a bold verdict on the innovation. He said: "WattDickie is beyond innovation. This is alchemy and apothecary.

"There was no hypothesis here, no grand plan, just an innate need to see what was possible.

"We went to the limits of brewing and took a match to them."