Is it True that some Scallops sold in fish markets are made from Skate Wings?

We can’t say that it’s never been done, but we doubt that it has been done very often. And surely few of us would continue to patronize a fishmonger or restaurateur who had been found to try such a trick.

At one time, skate was a low-priced fish caught accidentally (in the “bycatch”) by fishermen in pursuit of more lucrative quarry. But no more. Skate isn’t as cheap as it used to be, and the crime wouldn’t pay as well as it used to.

An even better reason to doubt this urban legend is the fact that running through the middle of a skate wing is a thin sheet of plastic-like cartilage.

A “scallop” with a layer of plastic in the middle wouldn’t be very convincing. It’s true that if the skate is big enough (the common skate can run up to 200 pounds), it can be filleted into two slabs, one above and one below the sheet of cartilage, and convincingly thick “scallops” could be punched out of each. But there are easier ways to make a dishonest buck.

If you ever decide to go into scallop counterfeiting, beware of the tiny, almost microscopic barbs on the skate’s skin. They don’t sting, but they prickle annoyingly. And don’t ask me how I know.

Known as raie in France, the skate is indeed a kind of ray, a term that covers several families of flat, bottom-dwelling fish that, like sharks, have cartilage instead of hones. Rays (family Rajidae) range from the most-often-eaten European skate (Raja batis) to stingrays with poisonous tails and giant manta rays that can weigh up to 3,000 pounds.

Rays’ bodies are flattened out into ribbed, fan like “wings” that undulate gracefully for locomotion. They are all edible, but some are not exactly gourmet fare.

Even if cookie-cutter cylinders of skate wing were to be passed off as scallops, they wouldn’t fool anyone who has ever eaten skate, sometimes sold as raja fish. The flavors and meat colors are similar, but the texture is all wrong. The skate’s toothsome, long-stranded texture is more like that of crab meat than scallop. Be suspicious of any scallop that seems to come apart in strands or layers.

And by the way, those little hollow, rectangular, leathery black ” mermaid’s purses” that you see washed up on beaches or tangled in seaweed are the egg cases of skates, originally containing two large eggs and abandoned after the young’uns have hatched.

With so much wing surface area exposed to the sea, rays would be at risk of having water extracted from their tissues into the saltier seawater by osmosis. As a defense against this potential dehydration, the rays’ body fluids contain a large concentration of a highly soluble, nitrogen-containing chemical called urea, CO(NH2)2 . Yes, it was first discovered in urine, but it is made synthetically.

Urea breaks down into carbon dioxide and ammonia, so rays, even the freshest ones, tend to smell of ammonia, normally an indication of spoilage in other fish. The ammonia smell can be expunged by soaking the fish in any acid, such as lemon juice or vinegar, or by keeping it refrigerated, or better yet, on ice, until all the urea is gone.