Crustacean (crayfish, prawns, shrimp, lobster)
Crustaceans are one of two main classifications of shellfish (the other being mollusks). They’re a class of arthropods which characteristically have segmented bodies. And they’re very, very tasty.
Crayfish (also called “crawfish”) are freshwater cousins of the lobster, found in most parts of the world. According to the comprehensive Web site “The Savvy Shellfish Lover”, at least 593 different species of these crustaceans have been identified, and there may be hundreds more to come. The most biologically diverse concentration of crayfish species in the world is found in the southeast United States. You can prepare them in the same style as lobster-steamed, boiled, fried, blackened, or baked. They’re a big favorite in Louisiana.
Prawns are basically really large shrimp, though there are regional differences of opinion about the distinctions. (In Europe and some Asian countries, prawns are considered large decapods with long antennae and toothed beaks, some varieties of which have slender bodies, with tails that don’t curve under as much as typical shrimp tails; but in the United States they’re just “big shrimp.”) One particularly desirable type is called the Black Tiger, a huge prawn that can grow to over a foot in length. Its name comes from the distinctive coloration of its shell: black with alternating bands of yellow. They’re usually sold frozen, with most commercial supplies coming from Asian shrimp farms.
Shrimp are one of about 40,000 known species of crustacea, the only group of arthropods that is primarily marine. They’re the most popular shellfish in the world and are probably one of the most popular varieties of seafood, period. And no wonder they’re lean, high in protein, rich in nutrients, and delicious; some might sayan ideal food.
Benefits of Shrimps
- First things first: Shrimp are a great source of protein, and a low-calorie one at that. One small 3 -ounce serving has 17 g of protein and only 90 calories. Shrimp have all nine essential amino acids, plus small to moderate amounts of nine important minerals.
- They’re relatively high in the important trace mineral selenium, with one 3 -ounce serving providing 46 percent of the Daily Value for this cancer-fighting nutrient.
- They also provide more than 30 percent of the Daily Value for vitamin D. I happen to think the Daily Value (400 IUs) for vitamin D is way too low, but 3 ounces of shrimp gives you 129 IUs of this cancer-fighting, bone-building vitamin, whose true value is only now beginning to be appreciated.
Shrimps and Astaxanthin
Then there’s astaxanthin. You probably never heard of astaxanthin, but it’s the main carotenoid pigment found in aquatic animals and is responsible for giving salmon their pink color. The thing of it is, salmon get most of their astaxanthin from dining on crustaceans like shrimp. Why should you care? Because this red-orange pigment, closely related to other well-known carotenoids like betacarotene and lutein, has stronger antioxidant activity than either of them (ten times higher than betacarotene, in fact). Studies suggest that astaxanthin can be more than 100 times more effective as an antioxidant than vitamin E. And shrimp are loaded with it. In many of the aquatic animals in which it is found, astaxanthin has a number of essential biological functions, including protection against oxidation of essential polyunsaturated fatty acids, protection against UV light effects, pro-vitamin A , Immune response, pigmentation, communication, and improved reproduction. In species such as salmon and shrimp, astaxan thin is considered essential to normal growth and survival and has been attributed vitamin like properties. We’re just beginning to understand its potential in human health, but there’s every reason to believe it’s really good for you.
are large crustaceans. They have hard shells and ten legs, two of which have developed into pincers. Although considered a gourmet food today, lobsters were so plentiful in the nineteenth century that they were used as bait for fish or even as fertilizer in the fields. Lobsters have firm, rich meat in their bodies, tails, and legs. You can also eat the lobster’s liver (known as “green tomalley”) or its roe (known as “coral”). Ounce for ounce, lobsters are somewhat similar to shrimp in nutritional value, with a few differences. Three ounces of lobster meat has about 95 calories and delivers almost 19 g of high quality protein, with all nine essential amino acids. It’s even higher in the cancer-fighting trace mineral selenium than shrimp is (3 ounces provides 56 percent of the Daily Value for this valuable nutrient), and in addition provides 32 percent of the Daily Value for zinc, plus small amounts of seven or eight other minerals. Unlike shrimp, it doesn’t have any vitamin D, but it’s one of the best non-animal sources of vitamin B12, with 3 ounces of lobster providing 50 percent of the Daily Value for that important B vitamin. Both shrimp and lobster have only about 1 g of fat per 3-ounce serving.
Shrimp and other shellfish have been given a bad rap for their high cholesterol content. But here’s the thing: The cholesterol in your food has minimal effect on the cholesterol in your blood, at least for the vast majority of people. Trans fat (and to some extent, saturated fat) raises blood cholesterol far more than cholesterol in the diet. One well known study, published in 1996 in the American Journal of Clinical Nutrition, actually tested a high-shrimp diet at Rockefeller University. They fed the subjects 300 g of shrimp a day. Blood cholesterol went up a bit, but HDL (“good”) cholesterol went up far more than LDL (“bad”) cholesterol, resulting in an improved cholesterol ratio. As an added benefit, subjects on the high shrimp diet saw a significant lowering of their triglycerides (a significant risk factor for heart disease). Bottom line: For the overwhelming majority Of people, the cholesterol in shrimp and related species isn’t a problem.
NOTE: As with mollusks, there is a potential for allergic reaction that you need to be aware of. But it’s also worth noting that seafood poisoning frequently masquerades as an allergic reaction. The take-home point: Get all your seafood from reputable sources, eat fresh, and prepare correctly.
Courtesy (150 Healthiest Food on Earth by Jonny Bowden)