For anyone who has faced the tedium of pulling off the shells from shrimp—particularly when serving a crowd—buying them already peeled may seem like a no-brainer. Especially since most times all you're doing is tossing the shells.
While it’s true that peeling shrimp takes time, we believe it’s always worth it to buy these crustaceans shell on. Furthermore, we often advocate for keeping, not discarding, the shells—and in a minute we’ll tell you why.
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The Composition of Shrimp Shells
But first, a little bit about this plasticky, translucent exoskeleton. Shrimp shells are made of a substance called chitin, which doesn’t break down when heated. (Chitin is also what gives mushrooms much of their structure.)
Beyond chitin, the shells contain proteins, sugars, and tons of ribonucleotides, which are water-soluble compounds that dramatically enhance savory umami taste. They are also rich in aromatic compounds that provide shrimp flavor.
Why You Should Always Buy Shell-On Shrimp
When shrimp is cooked in its shell (like in our Garlicky Roasted Shrimp with Cilantro and Lime recipe), that shrimpy goodness from the shell is absorbed by the meat, heightening its flavor.
An additional benefit is that shells shield the shrimp from heat. Shrimp can overcook and turn rubbery easily, but keeping the shell on helps insulate the delicate meat.
And even if you’re not cooking the shrimp in their shells, is it really worth buying them shell on? Still yes!
Virtually all shrimp undergo flash freezing on the boat. The shell provides protection to the shrimp during processing, freezing, and thawing. And they have much to contribute to the final flavor of a dish. Enter: Shrimp Stock.
How to Make Quick, Ultraflavorful Shrimp Stock
Shrimp stock is the ultimate use for your shrimp shells.
The compounds that we associate with shrimp flavor are highly volatile, which means they can infuse plain water with rich seafood-y flavor quickly. We’ve found that 5 minutes is all it takes to make a full-flavored shrimp stock from discarded shells.
To make that stock even more flavorful, brown the shells in a little bit of fat. Because many flavor compounds are fat soluble, the oil will pull those out and hold onto them, and in addition, the high-heat treatment activates the Maillard reactions, generating hundreds of new flavor compounds as well.
We peel the shrimp, use the shells to make a stock flavored with wine and thyme sprigs, and then gently poach the shrimp (along with red pepper flakes and plenty of garlic) in the stock. The result? Perfectly garlicky, spiced scampi that pairs beautifully with pasta or crusty bread.
Check out the full recipe below—and be sure to watch the latest episode of What’s Eating Dan? to learn even more about the science of shrimp.