Californian foie gras fans stuffed themselves at gastronomic last suppers this weekend, hours before a ban on the delicacy came into force after years of wrangling.

But even before the July 1 deadline, devotees of the prized French food – fatty liver, made by force-feeding ducks or geese – have been devising ways to circumvent the ban, dubbed 'foie-maggedon" by some.

While animal rights groups hailed the law which outlaws selling or making foie gras – pushed through by former governor and movie star Arnold Scwarzenegger – pro-foie gras supporters are not going down without a fight.

"I think many people are hopeful the ban will be reversed," said a spokeswoman for the two Michelin-starred Melisse restaurant in Santa Monica, which served a "Foie Gras for All" menu since January. The $185-a-head menu included foie gras and Dover sole, followed for dessert by "something sweet with foie" – foie gras ice cream. "They've been sold out all week and selling the all foie dinners to packed crowds," added the spokeswoman for Melisse, which has nevertheless vowed to comply with the new law.

From Monday anyone found selling or making foie gras in California faces a $1,000 fine, under a law passed in 2004 but which gave the state's only foie gras producer seven and a half years to comply.

In the run-up to ban, some of the Golden State's top chefs including Thomas Keller, the only American chef with two three Michelin-starred restaurants, redoubled efforts to persuade lawmakers to overturn the ban. Calling themselves the Coalition for Humane and Ethical Farming Standards (CHEFS), the group have staged a series of foie gras-rich evenings to raise money for the cause.

But John Burton, the former California legislator who drafted the law, has dismissed their calls, likening the tradition of foie gras to waterboarding and female genital mutilation. "I'd like to sit all 100 of them down and have duck and goose fat – better yet, dry oatmeal – shoved down their throats over and over and over again," he told the San Francisco Chronicle in April.

The law's entry into force is long overdue, said Paul Shapiro, vice president of the Farm Animal Protection of the Humane Society of the United States. "Seven and half years is a long time to allow a search for alternatives to the abusive force-feeding [of] ducks for foie gras. It's about time this basic anti-cruelty law take effect," he said.

While restaurateurs have overwhelmingly vowed to abide by the new law, ways of side-stepping the ban will no doubt be tested in the coming weeks and months.

It has been mooted that diners could bring foie gras with them to a restaurant, and pay a "Foie-kage" fee, the equivalent of corkage paid to bring wine to a restaurant. Others talk of private supper clubs, organized without any formal sale of foie gras – the new law bans only the sale and production of the delicacy, not its consumption or sharing between friends.

Mirepoix USA, which sells foie gras among other high-end French foodstuffs online, was urging customers to place "stock up and save" orders before June 28, noting that foie gras can be safely frozen and stored for up to two years. It has also launched a service where orders placed online can be picked up in neighboring Nevada, either in Reno or Las Vegas.

"Restaurants, specialty food stores, and individuals who enjoy foie gras hope that eventually the ban will be repealed," the company stated. "But in the meantime, Mirepoix USA has made arrangements to try to satisfy our customer's desire for foie gras, while still respecting the legislation."

France's foie gras industry body, CIFOG, said last week that California's law contravenes international trade law, adding that it had asked for a meeting with the French agriculture minister on Monday, the first day of the ban.

"Even if the financial impact is tiny, the decision by California really prejudices our image," said Marie-Pierre Pé, chief representative of the industry committee. "Since we respect the physiology of the animal, we cannot just let this go without reacting," she said, noting that the oesophagus of a goose or a duck has greater elasticity than that of a human.

Back in the United States, animal rights campaigner Shapiro holds that ordinary Californians will not lament the loss of foie gras from menus. "Most Californians have never eaten it, and many probably couldn't even pronounce it. While demand for foie gras is low, the cruelty involved in producing it is very high, and we're glad to see the law take effect."

- AFP, with Wine Searcher staff