Restaurants serve lobster in rolls, soup, ravioli and even on pizza – and diners are willing to pay a premium for the delicacy.

But an INSIDE EDITION investigation, which will air in full on Monday, has found that you might not always be getting the real deal.

INSIDE EDITION visited 28 restaurants around the county, including local seafood spots and national chains. Nathan’s, Red Lobster and even the Soupman – the New York eatery made famous by Seinfeld – were among them.

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The meat was scooped out from a variety of lobster dishes and sent off to a lab, where DNA tests were carried out to see if there was anything fishy about the lobster.

It emerged that in 35 percent of the samples, the lab found cheap substitutes instead of lobster.

A restaurant called ‘Get Hooked,’ just outside of Tampa, Florida, served up lobster rolls – but INSIDE EDITION found samples of the meat actually contained whiting, an inexpensive fish.

The owner told IE he did, “not purposely rip off the public.”

The restaurant owner says he makes his lobster rolls with a frozen mixture. It has some lobster, but he acknowledges it’s filled with other, cheaper fish like whiting and pollock.

And it wasn’t just local restaurants. At the country’s largest seafood chain, Red Lobster, INSIDE EDITION ordered lobster bisque soup from three different locations and scooped out the meat.

One sample included only langostino, a less expensive seafood more closely related to hermit crab than lobster, and two others had a combination of langostino and lobster. The FDA told INSIDE EDITION that soup with only langostino cannot be called lobster bisque. It must be labelled as langostingo lobster bisque.

In a statement, a Red Lobster company spokesperson said: “Red Lobster, the world’s largest seafood restaurant chain, serves a variety of lobster on its menu, including North American lobster, Maine lobster and langostino lobster.

"As a seafood expert, Red Lobster understands that the seasonality and availability of lobster can fluctuate, so our Lobster Bisque can contain meat from Maine lobster, langostino lobster, or, in some cases, a combination of both.

"INSIDE EDITION’s test was a matter of what we call 'the luck of the ladle' and both types of lobster provide the bisque with a rich, sweet taste that our guests love.”

At the world famous Nathan’s in Coney Island, Brooklyn, the lobster roll tested by INSIDE EDITION came back as whiting.

A Nathan's spokesperson told INSIDE EDITION: "Seafood fraud is a serious issue and Nathan’s Famous buys all of our lobster products from a member of the Better Seafood Board as part of our commitment to fair and honest sourcing. This is not a case of fraud.

"Lobster Salad is traditionally a mix, or salad, made up of seafood items. The main ingredient in our Lobster Salad is in fact Lobster. Any suggestion that it is not would be erroneous.

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"Nathan’s Famous 'Lobster Salad Sandwich' is made with a delicious, healthy mix of Lobster, Pollock and Whiting. Our sandwiches include a versatile and affordable blend of North Atlantic lobster meat and premium surimi seafood. We maintain a commitment to accurate labeling."

But there was some good news. Some samples, such as the lobster bisque from the Soupman, came back loaded with lobster.

New York City-based celebrity chef and best-selling author Rocco DiSpirito says there should be no compromise when it comes to lobster rolls.

They should be “all lobster, not a mixture of lobster and whiting and any other kind of fish,” he said. “The whiting, pollock thing is not what you'd expect when you order a lobster roll.”

DiSpirito is the author of "The Negative Calorie Diet," which takes a look at negative calorie foods that help fuel metabolism.

For more on the investigation, tune in to INSIDE EDITION on Monday.

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