I blame the English. For hundreds of years, the Scots and Irish made whiskey, and only they drank it. They didn’t market it to themselves, they didn’t have to, they were born drinking it.Then,in about the middle of the 19th century, London merchants decided the stuff might sell if they softened it by mixing in the light, almost flavourless whiskey made in Aeneas Coffey’s new stills. Blended Scotch was born, and with it international Scotch drinking and international Scotch marketing.This new whisky – then a brand new concoction – was marketed to people who drank, but who didn’t necessarily drink whisky or any other aged spirit. Although it was brand new, blended whisky wasn’t advertised that way. It was promoted as old. Why? Because what most people knew about ageing then is what most people know about ageing now: older is better.So,whisky was better than gin because it was aged, but also because it had an ancient pedigree; old whisky made by old methods in old distilleries; old, old, old.And older was always better. Age wasn’t positioned as a style difference, the way reposado and añejo tequilas are positioned, it was positioned as a quality difference.And because scotch is whiskey to most of the world, it set the standard for oldness.Ten years is good, 12 is better, 15 is posh, 18 is superb, 20 is sublime.American whiskey is on a different scale.Why? Two words:new barrels.Wood flavours are so much of what makes bourbon bourbon that only new barrels will do,but new barrels make it easy to over-do too. At some point, wood flavours overwhelm everything else.Four to five years old has long been the standard among respectable American whiskey brands. That hasn’t changed.What’s new is that almost all of the category’s recent growth has come from six to eight year old products, and increasingly older releases up to and exceeding 20-years, something unheard of 20 years ago.The present interest in older whiskey was sparked by two converging events. First, the bourbon sales crash, which began about 40 years back. That led to over-production, which created a pig-in-the-python of excess ageing stock.Second was the belated discovery of American whiskey by the rest of the world, which began about 25 years ago.One of the first countries to embrace American whiskey in a big way was Japan, already a big scotch market.Used to age statements on scotch labels, Japanese consumers wondered, “are there any twelve-year-old bourbons?” No, said their American suppliers, but there could be.“Back in the 80s, we were selling a lot of whiskey to Japan, more than in the United States.,” recalls Julian Van Winkle.“The Japanese market was clamoring for older whiskey so I sourced it out and supplied that demand.” Old whiskey wasn’t hard to find. The distilleries were overjoyed to have a market for it and let it go cheap.Van Winkle had his own Old Rip Van Winkle brand and also sourced and bottled old bourbons for other companies. He already had a 10 Years Old, created a new 15 Years Old for Japan, then a 20 Years Old for which he designed a new label honouring his grandfather, Pappy Van Winkle. Most of it was wheated bourbon from the Stitzel-Weller Distillery in Louisville, which his family had owned until 1972. ”I personally liked the older wheated bourbon so I was very excited to sell an older label.” When Van Winkle’s Kentucky distributor found out about the older products, he wanted to sell them too.Van Winkle wasn’t the only independent bottler buying low and selling high. Soon the distilleries got in on the action too.Thus were born double-digit bourbons. In 1991, a bar owner in Chicago told me he could no longer get Stitzel-Weller’s Very Very Old Fitzgerald (12 Years Old) because the Japanese had bought it all.Soon there were bourbons for all of the teen years, and a few at 20+. Soon there were extra-aged straight ryes too, such as Sazerac at 18 Years Old and Rittenhouse Very Rare at 21 and 23.Today, the cheap older whiskey that fuelled the boom (cheap at the producer level, that is; it was never cheap to consumers) is almost gone, but a taste for it remains. It is a thirst producers will continue to satisfy.So,how old is too old?Here’s what the master distillers think, and personally drink.“Dad enjoyed bourbon aged between six and eight years old,” says Jim Beam’s Fred Noe about his late father, Booker. “I enjoy bourbons aged from seven to 10 years old. For my taste, bourbons much older than 13 years old get too much wood.” Fred’s cousin,Heaven Hill’s Craig Beam,agrees exactly. “I still like bourbons that are aged seven to 10 years,”says Beam.“Anything over that I start to pick up lots of wood and oak, and the wood can overtake the grain notes.”When he does have a double-digit bourbon, he prefers it at high proof, like the 15-year-old, barrel proof Parker’s Heritage Collection Bourbon.For Wild Turkey’s Jimmy Russell, six to seven years is good, 12 is the peak, and anything older is usually too much.“Russell’s Reserve is 10 so you know where I think the best tasting whiskey is,”says Russell.Wild Turkey has done a 17-year-old and a couple of 15-year-olds, so how does he keep them from being toowoody? “With a limited number of barrels you can control it, keep that woody taste out of them,” says Russell.“You can pick barrels that are maturing more slowly.” Barrels for Wild Turkey American Spirit, the current 15-year-old, were eight or nine when they were chosen to go the distance.Jim Rutledge at Four Roses has a similar perspective.“I still believe the optimum period to age bourbon is between six and eight years,” says Rutledge. “Years and years of study, history and ongoing analyses uphold this fact.” Nevertheless, he acknowledges that it’s possible “to capture some very good quality bourbon barrels at older ages, but they are still the exception rather than the rule.” One distiller who doesn’t have a preference is Harlen Wheatley of Buffalo Trace who is, at 39, also one of the youngest master distillers and reflects what is, in part, a generational difference. “It very much depends on the occasion,” says Wheatley. “That’s why we offer so many different expressions.” “I am a fan of all the ages and I like trying to match up the event with the right bourbon.” Even bourbons or ryes that are more than 20 years old?“I have tasted some flavour-packed 23- year-old that was excellent,” says Wheatley.“I could see breaking that out for a special occasion.” The verdict? As with so many of life’s ostensibly simple questions, the answer to “how old is too old?”appears to be a firm, “it depends.”