BOGOTA, COLOMBIA - Yakup Ayden, the Dutch champion, has 15 minutes to prepare espressos, cappuccinos and his own signature drink for a six-member team of judges. (Juan Ferero/WASHINGTON POST)

When positioned at an espresso machine, Rob Kettner says, he pushes the very boundaries of producing a cup of coffee.

So as he prepared backstage for what in essence is the Olympics for coffee makers, Kettner tested a triple-decker brew tower. The contraption, complete with a scientific-looking coiling tube, takes eight hours to brew a liter of coffee. But the result is a “flavor manipulation,” as he put it, that just might give him the upper hand in four days of intense competition to determine who in the world makes the best coffee.

“This is not making a cup of joe,” said Kettner, 35, the Canadian champion, who is part owner of the Fernwood Coffee Co. in British Columbia. “It’s culinary coffee at its best; it’s real, true coffee; it’s the exploration of coffee and how far we can take it.”

He’s not the only one taking it seriously here in Bogota, capital of coffee central — the land of undulating, picturesque coffee farms and the iconic farmer Juan Valdez and his mule, Conchita.

In an event sponsored by makers of espresso machines and Colombia’s Coffee Growers Federation, the competitors came last week from Estonia and the Czech Republic, China and Rwanda. Each has his or her own style, technique and signature coffee drink.

BOGOTA, COLOMBIA - JUNE 02: At the World Barista Championship in Bogota, judges savor, smell, taste and grade the coffee prepared by some of the best baristas in the world. (Juan Ferero/WASHINGTON POST)

But they are all baristas (from the Italian for bartender). And in Bogota’s convention center, 54 of them are competing in the three rounds that make up the 12th annual World Barista Championship. The holy grail comes Sunday, with one barista achieving coffee glory (as well as snagging a Nuova Simonelli espresso machine and a trip to Brazil’s coffee country).

That means they take no chances.

The American, Pete Licata, 32, barista at the Honolulu Coffee Co., picks the beans from Hawaiian coffee bushes, then processes and roasts them himself. He has also made more cups of coffee than he could possibly count, he said, which helped him beat dozens of America’s best baristas and win a trip to Bogota.

“With competitions, you practice making cappuccinos over and over again,” said Licata, who wore a snazzy purple shirt, colorful tie and thick beard. “I would probably say I’ve made over a thousand drinks just in preparation for competition, you know.”

Wolfram Sorg, 35, a barista at Backyard Coffee in Frankfurt, Germany, arrived here with an entourage of supporters.

Spending a year to prepare for the competition meant choosing just the right coffee from Ethiopia, taking into account how much rain fell and how many days of sun there were in the growing season. Sorg went so far as to design his own water distillation machine. He enriches that water with aromas from raspberries, but the distiller means no salt, no other taste.

“We’ve been taking the long road here,” he said proudly.

Stefanos Domatiotis, a barista from Greece, serves a 'Capuccino' to the judges during the World Baristas Championship in Bogota, Colombia, Thursday, June 2, 2011. (AP Photo/Fernando Vergara) (Fernando Vergara/AP)

The real test comes in an arena that is a mix between a TV studio and a boxing ring. The fans (and in Colombia, there are plenty of fans) line the stands. Some bring flags, like those who traveled from as far as Romania or as near as Mexico.

Wearing an apron and a ready smile, each barista has 15 minutes to make espressos, cappuccinos and a drink of his or her own invention for four judges, all of whom take copious notes. Two other judges, meanwhile, stand inches away, making sure the techniques used to dose and tamp down the coffee are just so.

“You have to have very good technique,” explained Sonia Grant, a technical judge and founder of Kaffismidja, which roasts and makes coffee in Iceland. “You have to know your equipment completely, and know your coffee, and know how to grind the coffee to get a certain flavor.”

Moments after competing, Domas Ivonis, 22, admitted he had been a touch nervous.

Maybe it was the cameras, the clapping from the audience, the jaundiced look from a judge.

“I spilled milk, the milk was splashing,” Ivonis, who came from Lithuania, said almost apologetically. “I didn’t control it.”

Yakup Aydin, 27, from the Netherlands, whooped it up with his supporters after his 15 minutes before the judges. He had added a touch of blueberry to the foam in his coffee and a pinch of tamarind.

He could tell the judges liked what he was doing. He was in his zone.

“Actually, in my mind, I was back in Holland, doing my routine,” he said, “and the coffee was coming out great, so I was happy.”