David Goldstein
Reporting

When you order sushi -- how do you know what you're getting? How easy is it for sushi chefs to pull a bait and switch, and substitute for a cheaper fish?

We went to seven sushi restaurants in southern California.

We ordered tuna and snapper sushi and we took it to go. We bagged it up and packed it in ice. We sent it to Nova Southeastern University in Florida and their DNA lab for analysis. The results may surprise you.

At Todai in Studio City -- a worldwide chain of sushi restaurants with locations across the U.S. and in Japan -- we ordered red snapper and tuna roll. It looked and tasted just fine. But the DNA report told another story.

The tuna did come back as tuna. But the snapper turned out to be tilapia – a much cheaper fish.
A Todai spokesman apologized, saying the mistake resulted from the translation of the Japanese word "izumidai." They say it means fresh water snapper -- but it's really "tilapia."

At California Roll and Sushi Fish in Larchmont, another chain restaurant, we also ordered the tuna and red snapper. We were suspicious when the snapper was listed as "white fish" on the receipt.

And sure enough it came back as tilapia. The tuna was fine. The manager said it a "was a mistake on the part of the waiter."

At Benihana in Newport Beach, the red snapper again was the problem.

Tilapia.

Benihana also blamed it on the translation of izumidai. Because of our investigation they say they've removed the word "snapper" from the sushi listing.

At Kabuki in Hollywood -- another sushi chain -- the Japanese snapper was also tilapia. Again they blamed it on the translation.

In all 6 of the 7 restaurants we tested were tilapia was called snapper. Including GuGu Sushi in Hermosa Beach, where they thanked us for pointing out their mistake.

And at Shogun Sushi in Northridge, which never returned our call.

All of the tuna turned out fine.

Sugiura Toshi runs a sushi school in L.A. He says there's no mistaking the translation and restaurants could save a lot of money by substituting tilapia for snapper.

"It’s about $20 and this one from the package...its $4.50 a pound,” Toshi says. "They have to know it. The chef has to know. That's what you expect from the chef right?"

It’s also against the law.

"Tilapia is not snapper," says Dr. Jonathan Fielding.

Fielding is the director of the L.A. County Department of Health.

"Whether intentional or not people need to get what they order. We will look into this and talk to the restaurants,” Fielding said.