Fresh or frozen? Farmed or wild-caught? Domestic or imported? Shrimp is a staple ingredient for many of our favorite quick weeknight meals, so let's set a few things straight.
For matters of seafood sustainability, I always turn to the Monterey Bay Aquarium's Seafood Watch. According to their list, the best shrimp are wild-caught from the US, and more specifically the US Pacific Coast and up into British Columbia. After my experience in New Orleans, I'd also add Gulf Bay Shrimp to that list.
Ocean conditions along the US coast are closely monitored and fishing is closed if anything harmful is found in the water. This means you can be sure the shrimp you are buying are safe to eat. Improvements to the trawl nets by US shrimpers also mean that there is less shrimping by-catch.
Domestic farmed shrimp is a good alternative. If possible, check that the shrimp were raised in fully-recirculating systems or inland ponds. These are better for both the health of the shrimp and the surrounding environment.
The only shrimp to really avoid is the shrimp being imported into the United States. Foreign fishing and shrimp farming regulations can vary greatly from US standards and you can't always be sure of either the safety or the sustainability of what you're buying.
You can buy either fresh or frozen shrimp; both are fine choices. Fresh shrimp is highly perishable, so be sure it's within a few days of being caught. The heads and edges of the shells will start to turn black as the shrimp ages, so make sure the shrimp bodies are translucent and moist with no black edges or spots.
When buying frozen shrimp, check for ice crystals on the shrimp. This is a sign that the shrimp were thawed and re-frozen at some point, and this shrimp should be avoided. You'll also sometimes see black spots on the shells of frozen shrimp, but the Louisiana Seafood Handbook mentions that this is due to an enzymatic reaction and not spoilage.
Thaw frozen shrimp in the refrigerator overnight and then use it right away. Frozen shrimp with their shells still on tend to be of best quality and flavor. (Plus then you get the shells to make stock!) That said, "peeled and deveined" shrimp are super convenient and still very tasty.
Big or small? That's up to you! Shrimp size depends on the specific kind of shrimp and is not in itself an indication of quality or sustainability.
In the wild and crazy world of seafood sustainability and quality, shrimp is generally one of the safest bets. As always, ask questions, check packages, and buy the best quality seafood you can find and afford.
What kind of shrimp do you buy? Any recommendations?
Sources for Seafood Information:
• Monterey Bay Aquarium Seafood Watch: Shrimp
• Smart Seafood Guide from the Food and Water Watch
• Louisiana Seafood Board's Seafood Handbook: Shrimp
Related: What's the Difference? White, Brown & Freshwater Shrimp
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Unfrozen fresh wild shrimp are a rarity where I live but available on occasion and worth the price.
If you buy your shrimp at the grocery store, remember that anything they have out defrosted can be purchased frozen though you may have to buy two pounds or more (up to five lbs) if they won't open a bag for you. My supermarket often has the US wild caught but only defrosted (unless you ask and they'll toss a couple extra into the bag to make up for the frost). I'm wary of defrosted seafood at the grocery store, particularly in open displays where the items are not fully covered in ice. The closed displays without ice that fog up periodically are fine. I've bought 5 lbs bags at discount/wholesale chains or when there is a really good sale.
IQF Shrimp defrost in 10 minutes under a slight stream of running water if you forgot to take them out.
Shrimp can also sold in ice blocks of usually two lbs or more, and is one of the few foods that 'net weight' actually means drained weight, and doesn't weigh the frozen water. While harder to defrost, shrimp in ice blocks can be frozen for a longer period of time than the IQF shrimp which tend to get freezer burn or dehydrate with time. If I bought a 5lb bag of IQF, I portion it up in zip locks and add water to cover and freeze.
Since I hate peeling shrimp, I buy at least 16-20 count for cooking. Anything smaller, I only make boiled/spiced shrimp with so I don't have to deal with the peeling and share that job among the guests at the dinner. I never buy peeled or ez-peel, since they are usually treated with some sort of bleach/whitener or preservative.
Avoid any shrimp treated with any 'phosphate.'
Our Safeway has just started carrying wild pacific (BC, but I live in BC) shrimp and salmon. Makes me happy!
Actually, the Gulf of Mexico shrimp still has fairly high rates of by catch (unintended catch of fish, turtles and mammals). It's much better than many of the international fisheries, but not great. For your best option, although seasonal and highly local, look for spot prawns on the west coast, which are trap caught. Oregon pink shrimp (certified by the Marine Stewardship Council) and other cold water shrimp are a good option too. There are some smaller fishermen in New England catching northern pink shrimp. These are not the big shrimp cocktail style shrimp, but if we're talking about sustainability, they're the way to go.
and as Stan S. says any non-frozen shrimp at the grocery store is probably defrosted. All the farmed stuff comes frozen too.
I've had pretty good luck with the frozen wild shrimp from TJs. And WF often has small MSC shrimp that are really tasty
I don't trust imported farm raised shrimp at all. Seriously a disgusting product from many countries. I think they can be farm raised in a reasonable way I just don't know where you find them. Did cheap Asian imports kill the Southern domestic production a few years ago.
We have a neighbor & good friend who's a prawn fisherman here in BC, so when I get shrimp/white spot prawns, I get them from him. Sadly, hubby's allergic, so I don't get them often.
I grew up in Virginia, so always ate fresh caught Chesapeake Bay shrimp from a 'waterman' we knew. I'm definitely spoiled. Out in California now so this is good info! Had a great shrimp dish recently when my boyfriend surprised me by buying shrimp.
http://percentblog.blogspot.com/2011/11/recipe-shrimp-scampi-with-preserved.html
Always, always, ALWAYS Wild American Shrimp! I live in Florida, where we almost never have a shortage of shrimp, but you would be surprised at the amount of Vietnamese farmed shrimp there is in supermarkets. It's nasty stuff, if you do research on it.
Stick to Wild American!