Seafood 101: Scallops

The soft fleshy texture and delicately mild sweet flavor of scallops are enjoyed by even those who are not particularly fond of fish or other shellfish. The season for fresh sea scallops and bay scallops runs from October through March, while fresh calico scallops are available from December through May. Sea scallops and frozen scallops are available year-round.

Scallops are mollusks that have two beautiful convexly ridged, or scalloped, shells. They consist of two shells hinged at one end which is why they are known to marine biologists as bi-valve mollusks. The edible portion of the scallop is the white muscle that opens and closes the two shells and is called the "nut". The reproductive glands known as "coral" are also edible, although not widely consumed in North America.

• Health Benefits
• Description
• History
• How to Select and Store
• How to Enjoy
• Safety
• Nutritional Profile
• References

Health Benefits

Most people know that fish is good for you, but what about other seafood? As it turns out, scallops, in addition to their delectable taste, contain a variety of nutrients that can promote your cardiovascular health, plus provide protection against colon cancer.

A Nutrient Team for Better Cardiovascular Health

Scallops are actually a very good source of a very important nutrient for cardiovascular health, vitamin B12. Vitamin B12 is needed by the body to convert homocysteine, a chemical that can directly damage blood vessel walls, into other benign chemicals. Since high levels of homocysteine are associated with an increased risk for atherosclerosis, diabetic heart disease, heart attack, and stroke, it's a good idea to be sure that your diet contains plenty of vitamin B12 to help keep homocysteine levels low (homocysteine is also associated with osteoporosis, and a recent study found that osteoporosis occurred more frequently among women whose vitamin B12 status was deficient or marginal compared with those who had normal B12 status.) Four ounces of scallops contains 33.3% of the daily value for vitamin B12. In addition to their B12, scallops are a very good source of omega-3 fatty acids and a good source of magnesium and potassium, three other nutrients that provide significant benefits for the cardiovascular system. Omega-3 fats keep your blood flowing smoothly by preventing the formation of blood clots. Magnesium helps out by causing blood vessels to relax, thus helping to lower blood pressure while improving blood flow. Potassium helps to maintain normal blood pressure levels.

Protection Against Atrial Fibrillation (Heart Arrhythmia)

Eating scallops that are broiled or baked, but not fried, may reduce risk of atrial fibrillation, the most common type of heart arrhythmia, especially in the elderly, according to a Harvard study published in the July 2004 issue of Circulation. In the 12-year study of 4,815 people 65 years of age or older, eating canned tuna or other broiled or baked fish 1 to 4 times a week correlated with increased blood levels of omega-3 fatty acids and a 28% lower risk of atrial fibrillation. Eating broiled or baked fish 5 times a week lowered risk even more- a drop in atrial fibrillation risk of 31%.

Eating fried fish, however, provided no similar protection. Not only is fried fish typically made from lean fish like cod and Pollack that provide fewer omega-3 fatty acids, but in addition, frying results in the production of damaged, free-radical-laden fats in the fish as well as the frying oil.(December 13, 2004)

Protection Against Cancer

A high intake of vitamin B12 has also been shown to be protective against colon cancer. Vitamin B12 helps to protect the cells of the colon from mutations as a result of cancer-causing chemicals - another good reason to eat plenty of vitamin B12. So add scallops, a very good source of protein and vitamin B12, to your list of healthy seafood and enjoy.

A Canadian study published in the April 2004 issue of Cancer Epidemiology Biomarkers suggests that eating fish frequently may provide serious protection against three types of cancer: leukemia, multiple myeloma, and non-Hodgkin's lymphoma. Researchers compared the diets of almost 3,000 individuals with these cancers to those of 4,200 healthy controls. People who ate the most fish and who got most of their total fat calories from fish were 28% less likely to have leukemia, 36% less likely to have multiple myeloma, and 29% less likely to have non-Hodgkin's lymphoma. (June 30, 2004)

Description

Scallops are mollusks that have two beautiful convexly ridged, or scalloped, shells. Their two-part shell is why scallops are viewed by marine scientists as bi-valve mollusks. The part of the scallop that is generally consumed is the "nut," the white muscle that opens and closes the two shells. It has a soft, fleshy texture and a delicate flavor that may be mild or briny depending upon the variety. The "coral," the reproductive glands, are also edible, although they are not widely consumed in North America.

In the United States, the most widely available types of scallops include the Atlantic deep-sea scallop and the bay scallop. The flesh of the sea scallop is large, usually about one-and-a-half inches in diameter, while the bay scallop is tiny, averaging about one-half of an inch in diameter. In Europe, the most popular type is the great scallop, more commonly called Coquille St Jacques. Several hundred different species of scallops are found worldwide, in shallow areas of most seas. The Latin name of the common bay scallop is Agropecten irradians.

History

People have been enjoying scallops as a food ever since this beautiful mollusk appeared in the Earth's waters, basically since time immemorial.

The great scallop gained great prestige during the medieval era. Pilgrims visiting the shrine of St. James in Spain began to use empty scallop shells for both eating and begging. The scallop and its shell quickly became a symbol of this magnificent shrine with people using them to decorate their doorways as well as their coats of arms. In honor of the shrine, they were called the shell of St. James, now best known by their translated French name of Coquille St. Jacques.

Scallops are found in many waters throughout the world. The great scallop is abundant in the Mediterranean, while the sea and bay scallop are found concentrated in the Atlantic Ocean off North America.

How to Select and Store

Just as with any seafood, it is best to purchase scallops from a store that has a good reputation for having a fresh supply of fish. Get to know a fishmonger (person who sells the fish) at the store so that you can have a trusted resource from whom you can purchase your seafood.

Since scallops are extremely perishable, they are usually shelled, washed and frozen, or packed in ice, as soon as they are caught.

Fresh scallops should have flesh that is white and firm and have no evidence of browning. Frozen scallops should be solid and shiny, and the inside of their packaging should be free of frost. If you are planning on freezing the scallops, make sure to ask the fishmonger whether they are fresh or defrosted (if it is not clearly marked) since you will need to cook previously frozen scallops before refreezing.

Smell is a good indicator of freshness with fresh scallops being either odorless or having a slightly sweet scent. Since a slightly "off" smell cannot be detected through plastic, if you have the option, purchase displayed scallops as opposed to those that are prepackaged. Once the fishmonger wraps and hands you the scallops that you have selected, smell them through the paper wrapping and return them if they do not smell right.

When storing all types of seafood, including scallops, it is important to keep it cold since seafood is very sensitive to temperature. Therefore, after purchasing scallops or other seafood, make sure to return it to a refrigerator as soon as possible. If the scallops are going to accompany you during a day full of errands, keep a cooler in the car where you can place the scallops to make sure they stay cold and do not spoil.

The temperature of most refrigerators is slightly warmer than ideal for storing seafood. Therefore, to ensure maximum freshness and quality, it is important to use special storage methods so as to create the optimal temperature for holding the scallops. One of the easiest ways to do this is to place the scallops, which have been well wrapped, in a baking dish filled with ice. The baking dish and scallops should then be placed on the bottom shelf of the refrigerator, which is its coolest area. Replenish the ice one or two times per day. Scallops can be refrigerated for up to two days, although they should be purchased as close to being served as possible.

You can extend the shelf life of scallops by freezing them. To do so, wrap them well in plastic and place them in the coldest part of the freezer where they will keep for about three months. To defrost frozen scallops, place them in milk (or water) that has been boiled and removed from the heat. Alternatively, they can be placed in the refrigerator to defrost.

How to Enjoy

For some of our favorite recipes, click Recipes.

Tips for Preparing Scallops:

Scallops should only be cooked for a few minutes since exposure to too much heat will cause them to become tough and fibrous.

A Few Quick Serving Ideas:

Serve lightly cooked bay scallops with a salsa made from diced papaya, cilantro, jalapeno peppers and ginger.

Skewer marinated scallops, leeks and cherry tomatoes, and broil in the oven. Brush with garlic olive oil when done.

Add bay scallops to your gazpacho for extra flavor and nutrients. Healthy Saute scallops with ginger, shiitake mushrooms and scallions.

Safety

Scallops contain naturally-occurring substances called purines. Purines are commonly found in plants, animals, and humans. In some individuals who are susceptible to purine-related problems, excessive intake of these substances can cause health problems. Since purines can be broken down to form uric acid, excess accumulation of purines in the body can lead to excess accumulation of uric acid. The health condition called "gout" and the formation of kidney stones from uric acid are two examples of uric acid-related problems that can be related to excessive intake of purine-containing foods. For this reason, individuals with kidney problems or gout may want to limit or avoid intake of purine-containing foods such as crimini mushrooms.