One of the big boys of bourbon whiskies, Jim Beam, is going into sophisticated bourbon expressions with its latest release, Jim Beam Double Oak.

"Double Oak is a way of expanding our profile with a new flavour," says the brand's American whiskey ambassador Adam Harris.

Mr Harris, 41, was in Singapore recently for the launch of the premium expression, which is a permanent addition to the Beam Suntory-owned Jim Beam family.

Its repertoire includes the flagship Jim Beam Original, Jim Beam Black and Jim Beam Honey, among others.

But he describes Double Oak as an "extra bourbon-y bourbon" where the vanilla, caramel and oak flavours typical of bourbon are punched up.

This is achieved by letting the classic Kentucky Straight Bourbon Whiskey spend four years in a freshly charred new American white oak barrel before it is transferred to another newly charred barrel to mature a second time.

Jim Beam took a leaf out of Scottish whisky-making traditions, where whisky is sometimes aged in a secondary barrel. Twice-barrelling allows the spirit to have greater contact with the wood of the barrel. Along with the intense flavour, the whisky also becomes extra smooth.

How long Jim Beam Double Oak ages in the second barrel is not set. It is only removed for bottling "when it reaches the flavour profile we're looking for", Mr Harris says.

He describes it as a spirit more suited to the seasoned bourbon drinker. "Double Oak is indicative of a bourbon that has eight to 10 years on it," he says.

The choice to age the whiskey for a flexible period also mirrors the trend by whisky distilleries worldwide - and not just bourbon ones - to remove age statements from labels entirely.

Most distilleries started creating No Age Statement (NAS) whiskies as a way to manage dwindling stocks, by blending smaller volumes of older whiskies with younger ones.

As one of the best-selling bourbon brands worldwide, Jim Beam produces about 750 barrels a day and has adequate inventory "to navigate those waters pretty effectively", says Mr Harris.

But with a release like Double Oak, the focus is on the flavour and not necessarily the age.

"I think there's a lot of economics behind NAS whiskies, but there's also something to be said for drinking taste and not age," he adds.

"The onus is now on the blending process, making sure that the flavour profile is consistent from aged statement to no age statement."

The bigger and bolder flavoured expression is also the mass-market brand's reaction to growing global interest in bourbon, especially with the popularity of craft bourbon labels such as Pappy Van Winkle's Family Reserve and Four Roses.

Bourbon as a category has outperformed the Standard Whisky category globally in recent years.

Mr Harris, who spent the early part of his career as a bartender before joining Beam Suntory in 2006, credits bartenders with bringing American spirits back in fashion, with the stateside cocktail renaissance during the 1990s.

"Pre-Prohibition-style cocktails like the Manhattan and Old Fashioned were championed by bartenders, who brought the flavour of the spirit back into prominence," he says.

Hence he recommends having the bourbon in a Boulevardier or Manhattan cocktail to best capitalise on the extra flavour.

Jim Beam Double Oak is available in Singapore for about $80 a bottle at most bars and bottle shops, including online retailers such as Lazada and winesnspirits.sg.