Washington, D.C. blogger Sam Hiersteiner is a hot sauce fan turned maker. He's already harvested two pounds of chiles — serranos, jalapenos, and habaneros — from his 30-plant pepper garden this month, and he's ready to mash them into hot sauce as soon as more ripen. Last year, he mashed fifty pounds total.While he loved the results, he thought it would be even better with a whisper of the flavor imparted by a barrel used for aging bourbon.

But finding a used bourbon barrel hasn't been easy. Cocktail creators, beer brewers and home hot sauce makers are all seeking these barrels for their own experiments. Hard to find, expensive to ship, and often large enough to be called another piece of furniture, used whiskey barrels are becoming as difficult to find as a full bottle of Pappy van Winkle.

But recently, used barrel seekers and sellers have been finding each other in a mutually beneficial relationship that could be described as the ultimate in recycling.

The reason used bourbon barrels are so in demand has a lot to do with the very specific standards the makers of the sweet, smoky whiskey must meet. In 1964, a Congressional resolution declared bourbon a quintessentially American beverage, specifiying that 51 percent of the grain mash must be corn, and that it not be higher than 125 proof.

It also required that the charred, white oak barrels in which bourbon matures be used only once for aging the liquor — which takes anywhere from four to 25 years.But now these barrels have what can only be called a long and remarkable afterlife.

There are plenty of new charred barrels available online. Most coopersmiths (barrel makers)char the wood after the barrel has been built. That's what helps the flavor of the wood release into the liquor. Hiersteiner knew the char would be a good touch for his hot sauce, but the caramel and vanilla tones that are uniquely left behind in a barrel that's previously coddled some bourbon is what he was hoping for.

So Hiersteiner called distilleries near D.C., New York and Kentucky. He was stunned at the cost - as much as $200, plus the shipping was about $50, and then there was the issue of size. Most bourbon is aged in thirty gallon barrels. Some distillers use 15 gallon barrels, though far less frequently. Smaller, craft batches of bourbon are being fashioned in three (0.793 gallons) and five liter (1.32 gallons) barrels by artisanal whiskey makers, but they are harder to come by.

In any case, that's a lot of hot sauce. Hiersteiner estimates it would take more than 500 pounds of hot peppers to fill a 30 gallon barrel, and it needs to be filled to the brim, or it could dry out and spring a leak.

But it's not just the "chile heads" searching for smaller, used barrels. Visit any modern bar, the sort of place where the bartender is called a mixologist, and you might see a few. At Enzo Restaurant in Newburyport, Mass., Chef Mary Reilly and her team are serving up barrel aged cocktails with a local twist.

Enzo's team searched out used barrels, finally sourcing a five liter size from Ryan and Wood, a Massachusetts craft distiller of rye and rum. The size worked, although it's still a bit big. "Before committing to a five liter barrel, take a look at your consumption: Do you really want to drink only barrel-aged Negronis for the next year?" says Reilly.

One of Enzo's signature tipples, the Nonna Rose, a variation on the Rosita, is "gently aging in the barrel, gaining wisdom." The tequila and Aperol mix, with touches of dry and sweet vermouth and angostura bitters, emerges from the barrel with a "mezcal-like smoky note," according to Reilly, thanks to the flavors imparted by the bourbon.

When the barrels are used up, Reilly has a plan: "We are going to be trying aging in glass jars using barrel chunks."

The distillers are challenged in their quest for barrels, too. A recent article in The New York Times says that some American craft whiskey makers hope to use smaller barrels to try to speed up the aging process.

This will put more small barrels on the market, surely, and mixologists, home brewers and craft distillers are hoping that will make sourcing a little easier.

In Purcellville, Va., Scott and Becky Harris of Catoctin Creek Distilling will have 150 once used barrels at the end of 2012. Some will be sold to the general public for patio furniture and other decorative items, but most will go to area restaurants Boundary Stone and Mad Fox Brewing Company.

Recently, a perfect recylcing circle was created when a friend of the Harris' contacted another friend who owns a maple farm. Now, Pennsylvania-harvested maple syrup is being aged in used Catoctin whiskey barrels. And now, Langdon Wood Syrup is sold at the Catoctin distillery store.

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