The Forbidden Flavor That Makes Maryland's Blue Crabs So Coveted - Chowhound

What folks in the mid-Atlantic call "mustard" is also known as tomalley, and it is found in all kinds of crabs, as well as lobsters (in which it takes on a more greenish hue). Many sources have claimed that the mustard is simply the crab's fat, but this isn't the case. It's actually an internal organ called the hepatopancreas. It serves a similar role for crustaceans to what the liver and pancreas do for human…