Category Archives: Seafood is Safe to Eat

Is it OK to eat raw shellfish?

seafood is safe to eat

(printer-friendly version)

Eating raw or partially cooked oysters, clams, mussels and scallops poses openoystersignificant health risks for some people. Eating these raw or undercooked shellfish accounts for 85 percent of all seafood-borne illnesses. Shellfish need to reach an internal temperature of 145 F to be done. Just-opened shellfish are not fully cooked. A crinkled appearance to the meat typically indicates doneness.

The reason for the high incidence of illness from this handful of popular bivalves is simple. We eat them whole — digestive tract and all — and whatever microorganisms or toxins have accumulated in their guts reaches ours. As filter feeders, bivalve mollusks sit in one place and eat whatever the water brings them. If the water is contaminated by natural toxins, sewage or industrial pollution, so is the oyster, clam, mussel or scallop.

A naturally occurring bacterium, Vibrio vulnificus, poses a threat for people with certain medical conditions. Most infections occur from eating raw or partially cooked oysters. The bacterium can also enter the body through an open wound, cut, sore, puncture or burn on skin exposed to sea water or raw shellfish containing the bacteria. Vibrio vulnificus can be found in warm water along the coast, especially during the summer months. It does not pose any danger to most healthy people and can be killed by thorough cooking. Freezing does not destroy it. Nor does drinking alcohol or eating with hot pepper sauce.

Gastroenteritis usually occurs within 16 hours of ingesting the organism. Symptoms include chills, fever, nausea, vomiting, blood poisoning and even death within two days for people with weakened immune systems. More than 50 percent of infections from Vibrio vulnificus prove fatal for people with the health conditions listed here.

No major outbreaks of illness have been attributed to Vibrio vulnificus, but sporadic cases occur frequently.


People with any of the following medical problems are at risk and should not eat raw or partially cooked shellfish:

  • liver disease — from excessive alcohol intake, viral hepatitis, cirrhosis or other causes. This category accounts for most seafood-related illnesses and increases the risk of death more than 200 times.
  • gastrointestinal problems, including previous gastric surgery, low stomach acid, or low stomach acid from regular use of antacids
  • transplanted organs
  • chronic alcohol use
  • diabetes
  • immune disorders, including HIV infection
  • long-term steroid use, as for asthma and arthritis treatment
  • hemochromatosis and other iron disorders
  • inflammatory bowel disease
  • chronic kidney disease
  • cancer
  • heart disease and blood disorders

Older adults tend to be at increased risk because they suffer from these health conditions more often. Also, pregnant women, infants and very young children should eat fully cooked shellfish.

The best way to reduce the risk of illness is to keep within the seafood safety net. Never purchase shellfish from unknown or uncontrolled sources. They’re no bargain. Buy only from reputable dealers who buy from shellfish harvesters licensed under the National Shellfish Sanitation Program. If in doubt, ask to see the shipper’s tag that accompanies in-the-shell products. Also, ask to see the shipper’s number on shucked oyster containers. Such information tells who shipped the product and where it came from originally.

From: Mariner’s Menu: 30 Years of Fresh Seafood Ideas

Contributed by Joyce Taylor

Cooking Seafood


(Printer-friendly copy)

  • Rinse raw seafood under cold, running water to remove bacteria.
  • Always marinate your seafood under refrigeration, never at room temperature.  
  • Cook seafood thoroughly with a continuous heat source because interrupted cooking could promote bacterial growth.  Keep hot foods at 1400 F or higher and cold foods at 410 F or lower.
  • Never leave cooked seafood at room temperature for more than 30 minutes.
  • Cook seafood for 10 minutes per inch of thickness, and measure at the thickest point.  If baking, cook at 4500 F and deep fat fry at 3750 F.  Add five minutes to your total cooking time if your fish is cooked in a sauce or is wrapped in foil or parchment.  The U.S. Food & Drug Administration (FDA) recommends fish reach an internal temperature of 1450 F for 15 seconds.
  • The FDA recommends that in-shell oysters be steamed four to nine minutes or broiled three to five minutes after gaping.  Shucked oysters should be fried for three minutes at 3750 F; broiled, three minutes three inches from the heat source; baked, 10 minutes at 4750 F; or boiled, three minutes.
  • Clams should be steamed for four to nine minutes.

From: Mariner’s Menu: 30 Years of Fresh Seafood Ideas

Contributed by Barry Nash

Educate, Don’t Frighten Consumers


(Printer-friendly copy)

Seafood is an important part of a healthy diet because it is a good source of high-quality protein, is generally low in calories and fat, and has Omega-3 fatty acids that have many positive health benefits. The American Heart Association and Dietary Guidelines for Americans 2010 recommend eating at least two servings of seafood each week.

However, some consumers hear negative information about one type or species of seafood such as oysters and avoid seafood all together. In addition, food safety messages for certain “at-risk” groups are frequently misunderstood or followed by consumers who are not at risk.

Therefore, remind consumers that eating any raw animal food is risky, but cooking and effective post-cooking handling reduces the risk of foodborne illness.


How to reduce the risk of bacterial infection by Vibrio vulnificus is important for everyone. However, some helpful ideas for educating consumers are:

  • Consumers with weakened immunity such as diabetics, dialysis patients and individuals with liver disease, cancer or AIDS are advised to eat only thoroughly cooked seafood and avoid consuming raw seafood, especially oysters.
  • Stress that thorough cooking kills harmful bacteria and viruses in seafood, meat and poultry. Demonstrate the proper cooking of shellfish and/or provide cooked oyster recipes.
  • Obtain free consumer brochures from the Interstate Shellfish Sanitation Conference, or ask your physician or other health care professionals to provide free ISSC Vibrio vulnificus Fact Sheets.

Remember, thorough cooking of oysters will destroy the potentially harmful Vibrio bacteria!

Source: This information was provided by

Contributed by David Green

How Safe is Seafood?


(Printer-friendly version)

Seafood in the United States is now safer than ever, in part due to a federally mandated inspection program that began in 1997.

HACCP, or Hazard Analysis and Critical Control Point, is a science-based, food safety monitoring program used by the food industry to control the risks associated with certain food products.

Though retail markets remain exempt from the HACCP regulations, they are encouraged by the FDA to apply the same principles.

Even though seafood inspection programs exist, consumers also play a role in seafood safety. Choose your retail market carefully, and handle and serve food with care in your home. Here are a few tips when purchasing your fresh seafood at a local market:

  • Buy only from reputable sources.
  • Buy only fresh seafood that is properly iced or refrigerated.
  • Don’t buy cooked seafood if it is in the same case as raw seafood.
  • Don’t buy frozen seafood if packages are damaged or broken.
  • Get seafood home and on ice or refrigerated quickly.

Enjoy your fresh North Carolina seafood!

Adapted from: Mariner’s Menu: 30 Years of Fresh Seafood Ideas

Contributed by David Green

Seafood Allergens


(Printer-friendly version)

Approximately 2 percent of adults and 5 percent of infants and small children in the United States suffer from food allergies.

The cause is natural allergenic proteins found in food that can pose a health risk to sensitive individuals.

Symptoms include a tingling sensation in the mouth, swelling of the tongue and throat and difficulty breathing. More severe cases include hives, vomiting, abdominal cramps, diarrhea and a drop in blood pressure.

The eight foods defined as major food allergens are:

  • Milk
  • Eggs
  • Fish (e.g., finfish; salmon, cod and flounder)
  • Crustacean shellfish (e.g., crab, lobster and shrimp)
  • Tree nuts
  • Peanuts
  • Wheat
  • Soybeans

Food allergic consumers must learn to avoid those foods which make them ill.

For industry, the basic safety controls for allergens are product declarations (labeling) and monitoring in processing operations to prevent cross contamination among foods.

The Food Allergen Labeling and Consumer Protection Act of 2004 requires that all FDA-regulated packaged foods that contain a major food allergen to clearly identify the name of the food source.

For more information on seafood allergens visit the FDA website.

Contributed by David Green

Peppery Taste and Flushing of Skin



Histamine fish poisoning accounts for one third of all seafood-borne illnesses reported in the United States.

Histamine is present in various amounts in many foods. Fresh fish at harvest, however, are virtually free of histamine, but post-harvest conditions that allow for the growth of spoilage bacteria can result in histamine formation.

Human illness occurs rapidly after ingestion of fish with elevated histamine levels and lasts from several minutes to a few hours. Symptoms include allergic-like responses such as headache, dizziness, swelling of the tongue, nausea, vomiting, diarrhea and stomach pain. Histamine fish poisoning is usually self-limiting, and recovery is complete. Sensitive individuals may need to seek medical treatment.

Histamine is produced by certain spoilage organisms through action of enzymes which converts the amino acid histidine to histamine. The disease is completely preventable by proper icing of fish at harvest and maintaining iced conditions throughout distribution and storage.

For proper icing methods, read “How to Bring Home Your Fish” or for more information on histamine fish poisoning, go to Sea Grant

Contributed by David Green

In Like a Lion, Out Like a Fish!


Earlier this summer, the NC State University Seafood Laboratory and NC Sea Grant, in cooperation with the National Oceanic & Atmospheric Administration’s marine laboratory in Beaufort, NC, conducted a sensory evaluation on lionfish harvested off the North Carolina central coast.

Lionfish and pink snapper (also caught locally) were prepared with the herb seasoning profiled above.

Twenty individuals, who enjoyed eating snapper and grouper and liked the flavor of butter, basil and butter, were selected as sensory panelists. Each was asked to rate and compare the flavor, texture, color and appearance of both fish on a numerical scale of 1 (Terrible) to 7 (Excellent). The scores were statistically analyzed to discern significant differences.

The results showed the color and appearance of the two fish did not differ significantly, but the averaged scores for flavor and texture did significantly differ. Panelists’ comments indicated that half preferred pink snapper because of its firmer texture, and as a result, were inclined to rate its flavor as being slightly better than lionfish. Fifteen percent preferred the lionfish and 35 percent of panelists had no preference. The overall scores of both fish scored in the range of “Good” (5.0 to 5.9) to “Very Good” (6 to 6.9), indicating most of the panelists found both species appealing. This information suggests that lionfish has commercial potential as a food source.

Contributed by Barry Nash