Once the industry had perfected the art of blending to create consistent brands, there was no stopping its global ambition. As part of our occasional series from field to bottle, Ron Emler talks to two leading master blenders ...

For its first 300 years, production of Scotch whisky was very localised and infinitely variable in quality, but an invention in 1831 helped transform the industry and opened the way for it to become one of Scotland's biggest exporters.

The patent still of Aeneas Coffey could produce whisky at a higher degree of alcohol, with a lighter and more uniform character. His legacy was grain whisky made in continuous stills, and today Scotland's seven grain distilleries produce more than all its single malt distilleries put together.

The first 'blenders' discovered that by mixing malt and grain together, they could produce something a lot more consistent than an individual malt whisky at the time. And it was a repeatable art if they didn't have to rely on any one distillery.

Today's successors face the same challenge: to create consistent and high-quality blends, over fifty of which sell more than a million bottles per year. That is a testament to the ongoing skill of the blenders, who typically use between 20 to 40 different single malts in achieving their combinations of flavour and texture.

But it is the grain whisky that provides the structure and backbone of the blend, which, on average, comprises roughly 70% grain and 30% malt.

"It's my responsibility to set and maintain the formula of every blended Scotch whisky that Chivas Brothers produces," says Sandy Hyslop, director of blending and inventory.  "I must ensure they deliver the precise flavour profile for customers."

"For our classic expressions [notably the Chivas Regal range] we manage them year on year to be maintained as closely as possible to their original flavour style"

His counterpart at Diageo, Johnnie Walker Master Blender Dr Emma Walker, agrees.  "We need to make sure that every bottle our customers open, the dram they have in their hand, tastes exactly as they think it should," she says.

As the two biggest producers of Scotch, Diageo and Chivas Brothers between them have more than 15 million casks of spirit maturing so overseeing them is a task impossible for a single blender to undertake successfully. Both Walker and Hyslop have teams of specialists working with them.  Walker calls them her "12 lenses".

Over and above the duty of working with distillers to ensure supply and consistency of their existing ranges (occasionally making subtle tweaks as needed), master blenders throughout Scotland are also constantly working with brand development teams to lay down distillates for the future.

"It's about embracing innovation and experimenting", says Hyslop. "We explore different flavours and cask types and if an experiment yields something impressive, it may well be developed into a new product.

"With some of the distillates I lay down", he says, "I may not even see them mature into their final product."

"We continually ask ourselves how we can push the boundaries of Scotch whisky while staying true to its heritage and character."

He points to the recently launched, colourless Chivas Crystalgold. Legally, it is not a Scotch whisky but 'a spirit drink' targeted at the mixing and long drink market under the Chivas banner.

That, Hyslop says, took "years of collaboration with the blending team and extensive experimentation."

Meanwhile, Walker says, "We look at the characteristics produced in the distilleries. How will we mature them? We are setting up the inventories of the future to make decisions on whiskies we might never get to work with. How do we make sure we are looking at expanding our world of flavour?"

Research and collaboration with market analysts has seen Walker develop both Johnnie Walker Blonde and Black Ruby, each a different style and flavour extension. She sees more such innovations in the future to meet demands and opportunities in the ever-evolving markets.

So, is blending an art or a science? Can it be taught, or are its practitioners born with an innate ability?

Both Walker and Hyslop are graduates in chemistry. "You need to be eternally curious," says Walker. "You want to know how something is made, how it's put together and look at how you can change it. For me it [chemistry] helps to make sense of what's happening in the distillery and during maturation and how the flavours come together."

While a chemistry background helps, it is not de rigueur - a member of Walker's team is a trained environmental archaeologist, and Adam Hannett, the recently appointed master distiller at Bruichladdich, started as a distillery tour guide.

Hyslop says: "A natural curiosity and passion for Scotch whisky is essential. Without a genuine love for flavour, cask maturation and the patience this craft demands, one would struggle." 

"Blending demands years of dedication, discipline and practice," he adds. "What excites me most about blending is the sheer level of complexity and depth of flavour it offers.

"One of the most rewarding moments in the process is when the whisky is finally shared. There is something incredibly special about that first sip, when all the carful work behind the scenes becomes a sensory experience for someone else."

Apart from tending to their vast existing stocks, maintaining quality, experimenting, and laying down a spirit for the future, master blenders have a further key role in exchanging knowledge and spreading the gospel of Scotch.

Apart from the ability to nose flavours, blenders need to be able to describe them.

"A big part of the job is to talk about our whisky," says Walker. "It's not quite a brand ambassadorial role - I talk a bit more about technical detail. But it is vital to help consumers and our customers understand what we do, why we are looking at different flavours and styles."

"I have the joy of travel and meeting distillers, blenders and consumers from all around the world," says Hyslop. "These interactions develop my own palate and ensure we are in tune with evolving tastes and flavour profiles."