Tokyo ? Blowfish has long been a delicacy for the adventurous: Every year in Japan, a few people die after eating it.

Now scientists have put a school of pufferfish on a special diet and come up with a version that tastes just like the real thing — without the lethal consequences.

Eating pufferfish — known in Japanese as “fugu” — is not always so carefree.

The powerful poison tetrodotoxin is found in the ovaries, liver and intestines, and only specially licensed chefs are supposed to prepare the fish for human consumption.

Still, fugu is occasionally a last meal. Three diners died in Japan in 2003 from pufferfish poisoning after preparing the fish at home, according to government figures.

Researchers in Nagasaki, in southern Japan, are getting around the potentially deadly hurdle by examining the fish’s diet.

“We believed that pufferfish acquire poison by eating poisonous bait, such as starfish and shellfish, rather than producing it themselves. So we fed them nonpoisonous bait,” said Osamu Arakawa, a marine biologist heading the project at Nagasaki University.

He and his colleagues kept about 5,000 fugu on a strict diet of mackerel and other nonpoisonous food at seven locations along Japan’s west coast from 2001 to 2003. They also raised their specimens in water at least 30 feet above the sea floor or in purified tanks to minimize their exposure to toxins.

Arakawa says it worked. For two years, the group examined the fish each month, and they all tested negative for tetrodotoxin.

Japanese health officials are cautious. “The finding is a great scientific achievement, but it does not immediately mean we can guarantee food safety,” said Masanori Imagawa, a Health Ministry official. “When it comes to fugu, we can’t afford any mistakes.”

The fish could draw some diners who have long wanted to try fugu but feared the poison. Its meat is firm and light when served raw as sashimi, and succulent when cooked in a stew.

But some pufferfish fans are sure to balk. For many, the brush with death is part of the allure of the meal.

Takeshi Yamasuge, a fugu restaurant owner near Tokyo, chuckled when asked about poison-less fugu.

“Nontoxic fugu is boring,” he declared. “Fugu is exciting because it’s toxic.”