LOURDES GARCIA-NAVARRO, HOST:
If you make a lot of bourbon whiskey, you could distill a lot of profit. That's because bourbon sales in the U.S. are booming, up 36 percent in the last five years. But to age your new, pristine product, you need new wooden barrels. As NPR's Noah Adams reports from Kentucky, these barrels are becoming more precious than the bourbon.
NOAH ADAMS, BYLINE: It's a very old craft, a skill, almost an art. It's called cooperage. The Scots-Irish, who settled in Appalachia could do this. Cut the white oak boards into staves, steam them to bend, make metal hoops to hold the barrel tight. And coopering is now an industry. The barrels are made in factories. Inside, the air smells of fresh cut wood, and you can almost see the sounds.
(SOUNDBITE OF COOPERAGE FACTORY)
ADAMS: This cooperage is one of several owned by a company called Independent Stave. It's based in Missouri and it's the largest maker of whiskey barrels in the world. We've come to see the process in the small town of Lebanon, Kentucky.
(SOUNDBITE OF COOPERAGE FACTORY)
ADAMS: As the barrels take shape, they are carried, rolled, and conveyed, sometimes overhead, to the different workstations. Starting out as a collection of oak staves, they are fitted together, steamed, downed with steel, seared with flame. The barrels arrive at the end ready for inspection.
LEO SMITH: The barrel has water and air in it. They're looking for any kind of leak or defect in the barrel. He's going to fix that barrel. And if it's leaking, he's going to put a plug in that barrel where it's leaking - a small plug in it - to stop that week.
ADAMS: The plug is a simple piece of cedar widdled by hand. We're talking with Leo Smith. He is the supervisor for the last stop on the production line.
SMITH: Got to let the air and water out. Drain the water. Then it goes to this gentleman down here for another final inspect. And they go onto the trailers to distilleries.
ADAMS: Independent Stave is a family-owned company, and they don't talk much. I can't ask how many people work here in Kentucky, how many barrels they make. But the plant manager, Barry Shoemaker, does say in the last two years production has doubled.
BARRY SHEWMAKER: There's two shift a day, six o'clock in the morning till three in the afternoon. And at night we start at eight o'clock and we work until 4:30 in the morning. We've seen an increase, and it looks like there's no end in sight.
ADAMS: This company, Independent Stave, makes barrels for the big distilleries, Kentucky brand names you might have tasted. And so far, Independent is staying steady with demand.
But there's another need for oak barrels. If you're very small company starting to make bourbon or vodka, gin, rum, yours is called a craft distillery. Your output is low. It's kind of like a drop compared to the big brands. But somebody does have to make you some barrels.
KEVIN MCLAUGHLIN: My name is Kevin McLoughlin. I'm joint president of Calvin Cooperage.
PAUL MCLAUGHLIN: And I'm Paul McLoughlin, also joint president of Calvin Cooperage.
K. MCLAUGHLIN: Were both interchangeable.
P. MCLAUGHLIN: We're a team.
ADAMS: This is Kevin and Paul McLoughlin. The brothers moved here from Scotland. They own the Calvin Cooperage in Louisville. For more than 20 years, they've been crafting wine barrels and buying used bourbon barrels to fix up and sell to the whiskey trade in Scotland and Ireland. But now that this different market has come right to them, they're making white oak barrels for the newly rising craft distillers. Paul P. McLouhlin takes me to watch the charring process. They put oak scraps in the finished barrel, and soon you'll see the flames. In the beginning, it's called toast, and you'll be sniffing the char.
P. MCLAUGHLIN: You start smelling kind of a baked bread. See that smell? That's what we like. That's what we know we're getting a toast layer. And once we have the toast layer, we'll let the barrel ignite like that. You get your baked bread. You get kind of a marzipan, really, really nice smell.
ADAMS: The number of small craft distillers in the U.S. - it's going up fast. There could be 700 out there.
P. MCLAUGHLIN: Some of them call and say I'm making whiskey, I've got my stills going, and I need barrels. And I didn't think there would ever be a problem getting barrels.
ADAMS: At the Calvin Cooperage in Louisville, they are working overtime. But the company estimates that in this year to come, they could sell all the barrels they could make ten times over. Noah Adams, NPR News.
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