IS the recipe for traditional Scotch whisky about to change?

That's what many whisky drinkers are concerned about after Diageo revealed the existence of documents that look to shake up the well-known formula to the water of life.

Diageo, the largest producer of Scotland's national drink in the world, have suggested they may start maturing some malt in tequila casks rather than traditional oak. They've also been experimenting with using chocolate malt and even mixing low-alcohol versions of the well-kent tipple.

While Scottish whisky used to dominate the global market, making up 60 per cent of sales around the world, it has recently declined to 50 per cent. Facing the uncertainty of Brexit, the whisky industry is unsure of what lies ahead for Scotland's £4 billion industry.

It seems that Diageo's secret task force has decided to tackle market pressure by creating new forms of whisky - but they face a problem.

There are strict rules to how anything branded as Scotch is made: whisky must be distilled in Scotland from water and barley; it must be a least 40 per cent alcohol; and it must be aged for at least three years in an oak cask.

As many of the proposals from Diageo directly break these rules they will be seeking to change the laws around production - but they'll be facing resistance from the Scottish Whisky Association (SWA).

When Paul Miller, of Eden Mill Gin, attempted to make a whisky using chocoalte malt, the SWA told him that it might “lead to the production of a spirit which differs from traditional Scotch Whisky.”

Miller abandoned the project.

Speaking to The Herald, he said “I respect the job the SWA does in upholding the value of Scotch.” But he added: “It it has always been a pioneering industry. The challenge is to uphold the Scotch Whisky Act, while not restricting creativity.”

Miller believes the act, which sets out the laws for the making of Scotch, should be subject to periodic review.

He continued that: “We have the best educational institution for brewers and distillers in the world at Heriot Watt university. It would be a real shame for these people not to have an opportunity to demonstrate their creativity.”

Diageo insist that they are "unwavering" in their committment to maintaining the traditions of Scottish whisky. However they too believe that the current legal situation should not inhibit creativity and innovation.

A spokeswoman, also speaking to The Herald, said “As champions of Scotch, we are always looking at ways to innovate to both protect and secure the future success of the category.

“In doing so, we work with the Scotch Whisky Association on a range of ideas that seek to strike a balance between tradition and innovation, in a way that ensures consumers get the great products they want.”

A spokesman for the SWA said: “Scotch Whisky is a product renowned for its quality, craft and heritage. The regulations which govern the production of Scotch Whisky are the solid foundation on which the industry’s success is built, generating over £4bn in exports to almost 200 market worldwide in 2016.

“The SWA regularly engages with our membership on a broad range of ideas to ensure that the category is well-placed to grow in an increasingly competitive global market place.”