Crustacean Flavor

The aromas of boiled shrimp, lobster, crayfish, and crab are remarkable for their nutty, popcorn-like qualities, quite distinct from either mollusc or fish aromas. Even meats don’t develop these notes unless they’re actually roasted rather than boiled. They’re due to an abundance of molecules (pyrazines, thiazoles) that are normally produced when amino acids and sugars react at high temperatures (the Maillard reactions). These reactions evidently take place at lower temperatures in crustaceans, perhaps thanks to the unusual concentration of free amino acids and sugars in their muscle tissue. Among the amino acids that sea creatures accumulate in their cells to balance the salt in the water, crustaceans favor glycine, which has a sweet taste and lends sweetness to their meat.