Ulrich Steinhaus, a 34 year-old banker, washes down a roasted chicken with beer at Oktoberfest in Munich. He is wearing traditional Bavarian clothing of lederhosen and suspenders. (Michael Birnbaum/THE WASHINGTON POST)

The beer lovers at Oktoberfest brag about the centuries of history sitting in their mugs. But German brewers are increasingly worried that the old model may not be enough to carry them into the future.

Germans drink less beer every year, so breweries founded in the 14th century are searching for ways to compete in the 21st. The answer, increasingly, is to look to an uncomfortable place for German brewers who pride themselves as being the best in the world: America, which in Germany has a reputation for making beers that taste like water.

But in the United States, the market for unusual and inventive beer is growing. As German leaders try to stave off global economic crisis, they’re trapped between conservative impulses and a situation that appears to require radical solutions. German brewers, too, are struggling between pride in their long, steady history and the need to invigorate their bottom line.

Whether the average Wolfgang will go along with the efforts is another question. The mostly Bavarian revelers who were at Oktoberfest this week swore fealty to traditions that have connoisseurs from other countries looking elsewhere for inventiveness.

“One of the advantages of Bavarian beer is that it’s so old. It’s clean and natural,” said Florian Hiering, 20, who was sipping Spaten — founded in 1397 — from a mug that held a liter of beer. He had an ear piercing and was wearing soft brown lederhosen with matching suspenders.

“Bavaria is very conservative, and Germany is, too,” he said. “America is more open to experimentation.”

Those who attended the final days of Oktoberfest this week weaved through a pastiche of Bavarian culture both exaggerated and sincere: oompah brass bands, gigantic robotic tableaus of hunters who were roasting oxen on spits, and hundreds of smelly fish crackling on grills.

The celebration of unchanging traditions is big business for the brewers, but being stuck in time cuts both ways. Germans drank 122 liters of beer per person in 2002; in 2010 it was down to 107. Overall beer production sank from 10.8 billion liters in 2002 to 9.6 billion last year, according to the German Brewers Federation.

“We have to educate the consumer,” said Christian Dahncke, the head brewer of Hacker-Pschorr, another major firm, as he drank his own beer at the festival in his company’s tent, which can hold 8,200 people. “People grow up with the brewery. The father drinks Hacker-Pschorr so the son drinks Hacker-Pschorr.”

German beer generally sticks to a framework set down in a 1516 brewing law that is the oldest of its kind in the world: water, barley, hops and little more. Within the boundaries, there’s room for variation. But there’s little of the experimentation that takes place elsewhere.

“In America, what we’ve seen over the last 10 years is a growing subculture of brewing,” Dahncke said. “In Germany, we need more marketing pressure.”

He said that his company was opening a small-scale brewery this year to test new kinds of beers internally.

The conservative approach to beer is part of a broader caution toward radical reinvention in Germany — also on display in its approach to the debt crisis in Greece, economists say.

A patchwork of fixes to Europe’s economy, as leaders have tried thus far, may not be enough for 17 economies running at different speeds to share the same currency, economists say. They say the European system will need a radical rethinking if it is to function without setting off another crisis. That’s something that German political leaders and voters have thus far been slow to countenance.

“If you look through the economy, what Germans are good at is taking established ideas and making them a lot better,” said John Kornblum, a former American ambassador to Germany who still lives in Berlin. “They are the gold standard for all modern industrial products.”

But, he said, there are “outer limits of inventiveness. . . . They’re never going to produce a Steve Jobs, but they will produce lots of people who make really high-quality stuff.”

For beer drinkers, Germany continues to be a country to find predictably good drinks — not new ideas. Americans who have grown used to a pick of dozens of beers at their grocery store might be disappointed upon arrival in the birthplace of beer culture.

In America, “there is more beer diversity on the shelf than you will find in Munich or Prague or various other classic brewing centers,” said Julie Johnson, contributing editor at All About Beer magazine. “I don’t know if the German brewer is open to the kind of thing that we’re open to.”

In recent years, American brewers have tried making ever-more-unusual beers. Dogfish Head, near Rehoboth Beach, has tried replicating fermented drinks from ancient China and Egypt. Others age their beer in bourbon barrels to infuse it with the taste of whiskey.

In Germany, by contrast, the craziest thing that many brewers have done is add fruit flavors to their lineups.

“This beer has tasted the same for hundreds of years. I like that,” said Ulrich Steinhaus, 34, a Munich banker who was washing down half a roasted chicken with swigs of Spaten. He had swapped a suit for lederhosen with green suspenders and a strap across his belly.

“We try new things, but there’s nothing better than the old,” he said.

Special correspondent Eva Schroeder in Berlin contributed to this report.