This is the most expensive balsamic vinegar in America  — here's why 

Il Buco Alimentari

A 750-ml bottle of Screaming Eagle Second Flight Cabernet Franc Merlot out of Napa Valley, which has about four to five pours, is one of the most expensive wines at $706— but there is a balsamic that costs more.

Il Buco Alimentari in New York City — which opened in 2012 and serves as a sister restaurant and market to the famed Il Buco — sells the most expensive balsamic in America. Alimentari makes only 10 bottles available a year, with each 100-ml bottles (about the size of a small perfume) selling for $95 each, and there are only 10 bottles available every year.

The only way you can try it is to buy it.

"Typically, we sell one every two months, then in the Christmas season, we sell the rest," Danny Rubin, Alimentari's director, tells CNBC Make It. "It's more of a gift; I wrap it up beautifully. People like to get it to give to someone else."

The balsamic has a bittersweet taste and thick, syrup-like consistency. "After extreme aging, the vinegar has taken on further complexity and character and becomes dense and aromatic," Rubin says. "It's wonderful drizzled over roasted meats and vegetables, on vanilla ice-cream and panna cotta."

So what makes the 20-year-aged balsamic so expensive? It's the entire process.

The Alimentari process of aging balsamic 20 years starts in Italy until its 10th year, when it's transferred to Manhattan. Alimentari has an area with six barrels they call "batteria," each made with a distinctive wood to give the vinegar a specific flavor (there's chestnut, cherry tree, acacia, mulberry, juniper ash and durmast). Once a year, the vinegar is moved from a larger barrel to smaller barrel with successive pouring and refilling. During the transfer process, only a tiny amount of the vinegar is transferred (the barrels are never fully emptied). The smallest barrel contains the oldest balsamic.

"Each wood lends its unique flavor to the aging aceto, and each wood variety adds more complexity and richness," says Rubin. "This process take 20-plus years of aging to complete, not including the growing and harvesting of grapes. The longer the vinegar ages the thicker it becomes in consistency and richer in flavor. The price increases in correlation to the amount of years it has aged."

From the smallest barrel, they remove or "harvest" the single liter bottles of 20-year aged balsamic, all by hand. "We take out a liter and a half from the smallest barrel. That's all we're moving the entire year. In the same day, you transfer 2 liters from that barrel into the smallest barrel. You transfer 3 liters into the next smallest bottle. We do the entire transfer in one day in March every year. Over time, evaporation occurs and the balsamic ultimately reduces, thickens, and ages."

There are three categories of balsamic: Extra aged, aged and young.

Alimentari gets their balsamic from the Sante Bertoni vineyard in Montegibbio in the region of Emilia Reggio, Italy. Alimentari owner Donna Lennard has been working with the Sante Bertoni family for the last 20 years, using the Trebbiano and Lambrusco grapes grown on the vineyard.

"Balsamic is only balsamic when its from here, the way champagne is from the Champagne region of France," says Rubin. "So if you get California balsamic, it's not really balsamic. Trebbiano and Lambrusco grapes are indigenous to Modena/Emilia Reggio. They mash the grapes, which is unfermented juice, which is called must. They take the must and they boil that down. It's cooked and not alcoholic. After it's cooked, they add mother yeast, which causes the sugar to ferment, which turns it into vinegar."

Il Buco Alimentari

Rubin says there are no other places in Manhattan that age balsamic, and he is unaware of any restaurants internationally that have an in-house batteria.

"The vineyard could just send us 20-year aged balsamic to sell but it's really unique for us to age it for 10 years in house."

Originated in Italy, balsamic is a dark, viscous and intensely flavored vinegar made from grape must (unfermented juice). It has a rich and sweet flavor with notes of fig, molasses, cherry, chocolate or prune. Traditionally, it should pick up the flavors of the oak it matured in.

Food & Wine magazine says balsamic is the king of vinegars, and that the older a bottle is, the more expensive it is. The quality of balsamic matters; its sweet and syrupy flavor is almost impossible to reproduce any other way.

Traditionally, balsamic is mixed with olive oil for salad dressing and used as a topping for savory and sweet dishes, like sorbet, panna cotta, vanilla ice cream, cheese, berries or veal and risotto. It's not uncommon that really good balsamic is drunk as a palette cleanser or digestif in Italy. "Balsamic" connotes the vinegar's original use as a tonic or "balm."

"Twenty to 25 year extra aged balsamic is top of the line, the best years to get it, which is why it's expensive," Rubin says.

A regular 8-ounce bottle of balsamic can go from $5 to $30 at the grocery store. The most expensive balsamic is Oracolo Gold Cap. A 100-ml bottle goes for €350 ($412).

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