What's Imitation Crabmeat?

I'd like to try making crab cakes with imitation crabmeat. What exactly is imitation crabmeat? Does it contain ingredients that are not healthy? —S.P., Brooklyn, New York

Imitation crabmeat, also called surimi, is fish that is shaped, flavored and colored to resemble crab. It is typically made from Alaskan pollock, a lean firm fish with a delicate flavor. Both natural and artificial flavors are used as well as artificial coloring.