Heat liberates a yellowish-red carotenelike pigment in the shell. This chemical reaction changes the color of the lobster's carapace from (typically) bluish seaweed-green to ruddy red. Cooked shrimp shells also turn red. Even the surface of crustacean meat acquires a pinkish-red hue, though not as pervasive or intense as that of the shell.
**
Asian Recipes **