Pulque is the fermented and alcoholic juice of the maguey cactus, and these days, most clients prefer their pulque served with an infusion of fruit -- celery, mango, strawberry or peanuts -- so its tastes like a smoothie with a kick. (William Booth/TWP)

The ancient booze of the Aztecs has been losing its buzz over the past century, the victim of changing tastes, slander — and beer.

But salvation may yet come for the slightly viscous, naturally fizzy fermented juice of the maguey cactus, still peddled over the counter from big glass jars in the mega-metropolis of Mexico City, where on a warm Saturday afternoon, hazy old-timers can be found slurping down plastic buckets of the brew in a place where you urinate down a hole in the corner.

Yes, what might still save pulque (pronounced pull-kay) from the cultural rubbish heap are not its traditional consumers — the poor, the old, the rural — but young urban hipsters, who have taken to the antique drink as a kind of retro, subversive return to their pre-Columbian roots.

At the Pulqueria Las Duelistas in the shadow of the San Juan food market here — where butchers skin pigs and where sweet baby goats lay on the tile in their pre-taco state — a young crowd was packed inside, getting its Azteca on.

“It is cooler than beer and a lot cheaper than tequila,” said Jaime Torres, a 22-year-old design student and computer tech for an advertising agency who was getting pleasantly toasted with table of friends. “It’s old Mexico.”

A mural on the ceiling of Las Duelistas pulque shop. Murals are popular in the bars, as are shrines to the Virgin of Guadalupe. (William Booth/TWP)

Ancient, actually. Pulque comes from the heart of the blue maguey, or agave, cactus, which — when punctured at maturity — produces a sweet sap called aguamiel, or honey water. In the Codex Borbonicus from the 1530s, written by Aztec priests, there is a pictograph of the goddess of maguey, Mayahuel, with a pot of the frothy happy times.

The Spanish conquistadors turned up their noses. But what did they know? (They knew grapes.)

In 1886, one census counts 817 pulquerias in Mexico City, at a time when there were only 9,000 homes, according to Mario Ramirez Rancanio, historian at the Autonomous National University of Mexico.

At the turn of the 20th century, there were thousands of pulque joints. Every barrio had four or five. Today, optimists count 60, maybe 100, pulquerias in the city. Each year another set of swinging doors is shuttered as old owners die and the bars close.

“This place has been in business for 92 years, and I have six as the owner, and I have totally changed the image of the pulqueria, a totally new concept, with different clientele,” said Arturo Garrido, the proprietor at Las Duelistas. “Most of my clients are young, and it is my way to continue giving life to the pulque.”

His new concept: a killer jukebox, florid murals and waiters with ponytails, serving up a 100 percent natural buzz to a clientele that’s more lip piercing than hearing aid.

At La Risa, another popular pulqueria in the city center and perhaps the oldest in operation, a tour group stopped in for a few jars, which sell for 30 pesos a liter, or about $2.50.

“I heard it tasted like warm spit,” said Fernando Rivas, 28, a visitor from Colombia, “but that is a lie. This is delicious. There is nothing to be afraid of.”

On the jukebox, someone punched the Doors’ “Break on Through (to the Other Side).”

“My customers aren’t old anymore. Now they’re young people,” said Nabor Martinez, the owner of La Risa, who at 78 remembers when the beer was so cheap the breweries almost gave it away to get people to try it.

Today the pulque that is most popular is called “curado,” or cured, with the cactus ferment infused with fresh juices of strawberry or guava or celery. Like a smoothie, with a kick.

When breweries began to sell beer in Mexico, Garrido said, there were campaigns to disparage pulque as the produce of ignorant country folk — a kind of moonshine made by farmers who dropped a sackcloth of dung into the brew, while beer was a hygienic, sophisticated European delight.

In a report in the New York Sun in 1884, a correspondent wrote: “I have never seen so many drunken people as in the city of Mexico where the pulquerias are more frequent than gin palaces in London or gin mills in the Bowery. It is the bane of this favored land.”

Everado Gonzalez, director of the 2003 documentary “Pulque Song,” about an old-school establishment, fears the drink will continue to struggle to survive.

“Pulque is alive,” he said. “It’s like yogurt, it’s delicate, and you can’t bottle it or can it or export it.”

A company that tried in the 1970s found that the product kept fermenting in its cans and exploded.

“A pulqueria is not a cantina. It’s not a bar,” Gonzalez said. “It is a refuge, or was, for the lowest classes of society. Your drink is cheap. You are not sitting at a table, with good manners. You don’t need a table. You sit on a bench, where you can do what you want, say what you want.

“It was a beautiful island of freedom.”

Researcher Gabriela Martinez contributed to this report.