On the edge of the Campo de' Fiori open-air market, the question on the mind of Ruggero Ruggeri, a 70-year-old grocery store owner, was this: What does someone at the European Commission in Brussels know about buffalo mozzarella, a genuine Italian article?

Italian shoppers want their fresh cheese floating in brine, which keeps it moist, Ruggeri explained this past week. And they want to be able to tell their grocery man how much to slice off the big pearly white "braids" of the cheese.

Instead, because of European Union rules that came into force two years ago, mozzarella must be packed in plastic with the expiration date stamped all over it. "Mozzarella loses all its flavor sitting in a plastic bag," he declared. "And how can we cut it to order? Our clients have complained. People don't like it anymore."

Similar resentment is resonating throughout the E.U. these days, as the bloc faces a rebellion from within by people who say it has grown too big, too fast and become unaccountable now that it oversees 25 countries with a population of more than 450 million. The objections vary from country to country, but they add up to the same thing, a desire to put the brakes on more than 50 years of integration.

In France, voters rejected a proposed E.U. constitution May 29 by a ratio of 55 to 45. In the Netherlands, another founding member of the bloc when it was formed in 1952, it was rejected 62 percent to 38 percent three days later. Few voters had actually read the voluminous document, but a "no" vote was a way to protest against the integration that has been a pet project of political elites for half a century but has rarely been put to the citizenry.

Many of the constitution's opponents say they favor a united Europe. It has made cross-border travel easy, and it has provided the convenience of a common currency in 12 countries. Many people believe it has helped make their standard of living among the highest in the world and kept the peace between member countries for more than half a century.

But opponents fret that the push for uniformity threatens local customs and cultural quirks that add up to a way of life.

In France, "no" voters often said they were convinced the E.U. would impose what is known derisively as Anglo-Saxon economics on all its members, effectively dismantling the French welfare state with its emphasis on job preservation and a generous social safety net.

For other opponents, the issue was immigration. They believe that their countries' Muslim minorities are already too large and that the constitution would eventually open the way to admission of Turkey, a predominantly Muslim country of 70 million people.

Other concerns are provincial, but still arouse emotion. Some Hungarians, for instance, fear the E.U. will over-regulate the way they have traditionally force-fed geese to produce foie gras. In Spain, people raise the specter of an E.U. mandate to outlaw bullfighting.

"All the E.U. regulations changed the way we do business," said Ruggeri, whose store is a Rome landmark.

The man who works the cheese and meat counter in a white apron said he was not aware of any epidemic resulting from the traditional way of selling mozzarella that would justify the packaging regulation.

"Then there's cod," he complained. "You can't sell it moist and by the piece anymore. It has to be dry and customers are forced to soak it at home."

He was just getting started. "Ah, and they changed the rules for mascarpone. It now has to be split up and packaged into regulation amounts, like a quarter kilogram, or half kilogram. We used to keep it on hand melted and spoon out just the amount the customer wanted."

"All summed up, I have a negative opinion of the E.U.," said Ruggeri. "I wish Italy could withdraw. I don't know what we gained other than an E.U. passport."

Dutch Hashish Bars

Arian Klunder, 26, has a habit of regularly smoking joints at his job in Amsterdam. His boss, in fact, encourages him to get high with the customers. It's a perk that comes with being manager of the Kadinsky coffee shop, one of the many marijuana-and-hashish bars that contribute to the Dutch city's anything-goes reputation.

The coffee shops, as the pot parlors are euphemistically known, are technically illegal but have long been tolerated by the Dutch government. Recently, however, a nightmare scenario has been spreading through the herb-scented haze. Could the E.U. force the Netherlands to crack down on its cherished drug dens?

Although Dutch officials have told citizens not to worry, the mere idea that European Commission bureaucrats in Brussels might interfere with his livelihood was enough to persuade Klunder, 26, to cast a ballot against the proposed E.U. constitution. "Even the chance that it could happen is enough reason to say no," he said.

Dutch opponents also speculated that the E.U. would eventually override the country's permissive policies governing abortion, euthanasia and drug use.

Local lawmakers who campaigned on behalf of the constitution tried to reassure voters that the country's sovereignty was not endangered. "Each country has its own culture, each country its own national identity. Brussels does not touch that, and rightly so," Justice Minister Piet Hein Donner wrote in a pre-election letter to the newspaper De Volkskrant.

But many voters were not convinced, including Klunder. He noted that the constitution would erode long-standing E.U. principles that a single country can block legislation. A small one like the Netherlands would be left at the mercy of its neighbors, he said: "Holland only has a very small voice."

"If you would close the coffee shops in Amsterdam, the economy would crash," he added. "It's not just backpackers with three dollars in their pockets. It's businessmen and regular people who come here to relax and smoke a joint and spend money. We could still make money with cheese and tulips, but coffee shops are a lot more lucrative."

Britain's Pound

Financial gripes against the E.U. resonate in Britain, which so far has resisted calls to give up the pound sterling in favor of the euro.

Tim Martin, the 50-year-old founder of JD Wetherspoons -- a chain of 650 pubs across the United Kingdom -- financed a $70,000 campaign four years ago against proposals for Britain to adopt the euro. The money paid for thousands of beer mats, mugs and posters that featured the euro symbol and the slogan "Let's Get Shot of It."

His opposition hasn't faded. The source of his resentment? Memories of a 1992 currency crisis, when the British pound and other European currencies, linked in a pre-euro effort to regulate exchange rates, plunged in value.

"We had doubled our profits that year, but the banks in a panic started calling in all loans," he recalled. JD Wetherspoons survived and has expanded rapidly since then, but the episode left Martin with a deep distrust of economic integration. "I am not an economist; I am a pragmatist," he said in a telephone interview. "And I cannot see that a single currency will ever work without a single government to administer it and with tax-raising powers."

These days, the British are among the strongest skeptics of further European consolidation. Prime Minister Tony Blair's government had pledged to hold a referendum on the E.U. constitution sometime next year, but has hedged on its plans since the French and Dutch rejections of the charter.

A decade ago, many people in Britain saw adoption of the euro as inevitable, but Martin said the tide has shifted. "Now there is a change," he said. "People say they don't want it. They are fed up of Europe."

Whitlock reported from Amsterdam. Special correspondent Glenda Cooper in London also contributed to this report.

Ruggero Ruggeri, a grocer in Rome, says the E.U. "has changed the way we do business" because of regulations governing the packaging of certain goods.