Does whisky have to evolve, change even, to secure a future? The debate is common to all three of the great traditional whisky markets in Scotland, Ireland and America. And it’s one that is regularly reassessed and reconsidered in all three countries.On one side of the argument are the traditionalists, the ‘don’t fix what’s not broken’ brigade, arguing that whisky’s core characteristics are the very thing that make it stand apart and therefore best ensure its future.On the other side are the modernisers, who argue that the fickle modern customer wants innovation and exciting new products, and that without change the existing whisky will disappear and the next generation will have lost interest. New and growing markets in the East and India are giving the overall picture an artificially bright hue, they argue, but they can’t carry the sector forever.So far in Scotland at least, an uneasy truce has held firm between the two camps. The traditionalists have successfully held out to protect the simple definition of what Scotch is, without it being diluted. The modernisers meanwhile have contented themselves with special finishes, unusual cask types, cask strength and unchill-filtered bottlings and with tinkerings with the fermentation and distillation process.But the variety on display in Scotland isn’t matched in America. Heaven Hill and Buffalo Trace have invested in innovation to some extent, there have been small batch and single cask bottlings and the likes of Wild Turkey have dabbled with special finishes.So why not? Is it that bourbon, with its dominant new casks, its awesome temperature extremes and its fast track maturation process, doesn’t lend itself to special finishes?On the face of it Labrot & Graham wouldn’t seem to be the sort of place to house innovation and invention.Set in the heart of horse-breeding country and skirted by neat stone walls and pretty little white fencing and rich green fields, it’s quintessentially old Kentucky.But innovation here shouldn’t surprise anyone. For it is on this site that the modern bourbon process was developed and defined, and where James Crow and Oscar Pepper perfected whiskey-making techniques including the sour mash process.Pass through its doors and it’s glaringly plain that this is no traditional distillery.Instead of ugly column stills there are pretty and pristine copper pot stills, imported from Scotland and used to make bourbon. Labrot & Graham is the only bourbon maker to do it this way and it didn’t happen without a great deal of sweat and heartache.This is the home of Woodford Reserve and now Chris Morris, Kentucky’s youngest and newest distiller, is setting the cat among the pigeons once more – this time with the launch of a Woodford Reserve finished in Californian wine casks.This is a highly controversial move.Bourbon producers like to emphasise their heritage and history, and to highlight the uncompromising way that their spirit is produced. Woodford Reserve, for instance, is sold as one expression and one expression only. There’s a view that it’s not to be messed with.But two years ago the distillery launched the first of a new Master’s Collection series, called Woodford Reserve Four Grain. It was just that: a bourbon made with the required minimum 51 per cent corn, but made also with malted barley, rye and wheat – a total of four grains rather than the normal three.The first effort was bold, oily, and a touch immature and grassy. The second batch was a revelation.So before we dismiss the new version out of hand, we should at least approach it with an open mind – not easy because while Four Grain was a variant on a theme, the new whiskey is unashamedly a departure in two new territories.Called Woodford Reserve Sonoma-Cutrer, the whiskey is finished in Californian Chardonnay and as yet it hasn’t reached Europe. It may never do so, because only 900 cases have been released and the Four Grain was snapped up by collectors in no time at all.And it’s not clear either what Woodford owners Brown-Forman is up to.Is this a way of humouring the master distiller and letting him out to play, or a tentative toe-dipping to test the water before taking whiskey in to new and unchartered territory?Certainly it’s not without risk. Awhile back the publicist at Woodford Reserve’s sister distillery Jack Daniel explained that you just don’t mess with a traditional process.“We ain’t gonna kick a pulling mule,” he said.Sonoma Cutrer might not exactly be a kick, but it may well be considered a sharp prod.Both the traditionalists and the modernisers will be watching closely to see how the mule reacts.