illustration Valentine dinnerOysters and champagne. Love is in the air. It must be Valentine’s Day.

Yes, indeed, oysters have long been associated with romance — the perfect aphrodisiac.

There’s actually some science to back that up, although it’s about the way rats, not humans, responded to oysters in a 2005 study done by a team of Italian and American researchers. The results were so astounding that when they were made public, it was headline news.

According to, “Are oysters really aphrodisiacs or just a Valentine’s Day marketing ploy?” researchers found that oysters and other bivalves, such as clams and mussels, contain rare amino acids that are not commonly found in nature.

These two amino acids — D-aspartic acid and N-methyl-D-aspartate — play a part in the synthesizing of hormones.

Turns out that D-aspartic acid temporarily increases testosterone levels and improves sperm motility. In addition, the second amino acid can increase neural excitably.

When the scientists injected rats (nope, it wasn’t on Valentine’s Day) with these amino acids, the males experienced an increase in testosterone production. And in a fitting partnership for romance, the female rats increased production of progesterone. Both of these hormones increase libido.

And though the results of the tests looked promising, some scientists pointed out that the animal studies might not pertain to humans, which to them meant that it’s difficult to conclude that oysters and bivalves boost sexual desire in humans.

Even so, many oyster lovers smile knowingly at the truth of it. After all, if people associate oysters with “love,” who’s to say that that isn’t an aphrodisiac in its own right.

Oh, so healthy
Another plus in oysters’ favor is how high they are on the nutritional scale. They’re low in saturated fats aka “bad fats,” and high in “good fats” such as omega-3 fatty acids.

listeriaheart-iphoneAnd speaking of hearts, as we often do on Valentine’s Day, when oysters are eaten in moderation, they can help lower cholesterol levels and reduce the risk of heart disease. (“All the better to love you, my dear.”)

The list goes on. Oysters provide a lot of vitamins and minerals — iron, zinc, copper and vitamin B-12. As for iron, 100 grams of shellfish contains about 7 mg of iron, compared to only 2.6 mg in the same amount of beef or lamb.

And getting back to the role oysters can play as an aphrodisiac, zinc promotes sperm production — 100 grams of oysters has about 80 mg of zinc compared to 8 mg in the same amount of beef.

And if your true love is the environment, it’s good to know that an adult oyster is capable of filtering 25-50 gallons of water a day. With filtered water, comes more seagrass, which is a feeding and breeding ground for other species such as rockfish and crabs.

Oh, and besides all of that, oysters are just plain delicious (at least in this reporter’s opinion). Many people wouldn’t think of going without them when celebrating holidays like New Year’s Eve, Cinco de Mayo, Fourth of July, and, of course, Valentine’s Day.

Keeping it safe
But before popping the champagne cork, make sure the oysters you’ll be serving, or dining on, won’t send you and your valentine to the emergency room — dehydration from vomiting and diarrhea doesn’t make for anyone’s version of a romantic time.

Other symptoms of food poisoning can include stomach cramps, muscle aches and fatigue. People experiencing severe symptoms, which can start as early as 12 hours after eating oysters, should contact their doctor.

raw-oysters3-iphoneRaw or cooked?
That’s an important question since raw oysters can be contaminated with a variety of foodborne pathogens such as E. coli, norovirus and Vibrio vulnificus to name a few. The Vibrio bacteria, which is generally found in the warmer Gulf Coast waters during the summer, can be life-threatening, even fatal, when eaten by someone with liver disease, diabetes or a weakened immune system, according to the Food and Drug Administration.

On the West Coast, warm temperatures during the summer can trigger Vibrio parahaemolyticus, a bacteria found naturally in the environment. When midday low tides coincide with warm weather, the bacteria can grow quickly, raising the risk of vibriosis illness among people who eat raw or undercooked oysters.

FDA oyster myth busters

MYTH: Eating raw oysters are safe if you drown them in hot sauce, which kills everything.

Fact: The active ingredients in hot sauce have no more effect on harmful bacteria than plain water. Nothing but prolonged exposure to heat at a high enough temperature will kill bacteria.

MYTH: Alcohol kills harmful bacteria.

Fact: Alcohol may kill your good judgment, but it doesn’t destroy harmful bacteria in the food you eat while drinking it.

MYTH: Raw oysters are an aphrodisiac and will cure a hangover.

Fact: There is no scientific evidence that either of these commonly held beliefs is true.

MYTH: Avoid oysters from polluted waters and you’ll be fine.

Fact: Vibrio vulnificus in oysters has nothing to do with pollution. Rather these bacteria thrive naturally in warm coastal areas, such as the Gulf of Mexico, where oysters live.

MYTH: An experienced oyster lover can tell a good oyster from a bad one.

Fact: Vibrio vulnificus can’t be seen, smelled, or even tasted. Don’t rely on your senses to determine if an oyster is safe — or any other food is free of bacteria or other pathogens.

MYTH: Just a few oysters can’t hurt you.

Fact: Roberta Hammond, the Food and Waterborne Disease Coordinator for Florida, cites a case where a fatality caused by Vibrio vulnificus occurred after the victim ate only three oysters. The seriousness of any case depends on many factors, including how much bacteria is ingested and the person’s underlying health conditions.

MYTH: Avoid raw oysters in months without the letter “R” and you’ll be safe.

Fact: While presence of Vibrio vulnificus bacteria is higher in warmer months, according to the Centers for Disease Control and Prevention, a full 40 percent of Vibrio infections occur during colder months from September through April.

Selecting your oysters
Whether your choice is raw or cooked oysters, here are some tips from the FDA about how to select them.

Look for the label: Look for tags on sacks or containers of live shellfish still in the shell and labels on containers or packages of shucked shellfish. These tags and labels contain specific information about the product, including the processor’s certification number.  While some oysters are harvested and processed in accordance with national shellfish safety controls, that information may or may not be on the label. If sellers don’t have any tags to show you, don’t buy their oysters.

Discard cracked/broken ones: Throw away oysters, clams and mussels if their shells are cracked or broken.

Do a Tap Test: Live oysters, clams and mussels will close up when their shells are tapped. If they don’t close when tapped, do not select them.

Storing oysters
Always keep oysters, and other shellfish, cold before cooking or serving them. That’s important because foodborne pathogens reproduce quickly in warm temperatures, and even more quickly once they’re in your system.

With that in mind, put oysters on ice or in the refrigerator soon after buying them. If you’re going to transport the oysters in a picnic cooler, be sure to wash it with hot soapy water before putting the ice and oysters into it — and again before using it for anything else.

Never leave oysters, or other perishable food, out of the refrigerator for more than two hours, or for more than one hour when temperatures are above 90 degrees F.

cooked oystersCooking oysters
Even though raw oysters on the half shell are extremely popular, many health officials warn that no matter how many safeguards producers follow, there’s no way to assure buyers that the raw oysters are safe to eat. Only heat can do that.

For that reason, they recommend that oysters be cooked, and that means cooked all the way through to a temperature of 194 degrees F for a minimum of 90 seconds. But since poking a thermometer into a batch of oysters isn’t always all that practical, they offer these tips

  • If you put the unshucked oysters into a pot of boiling water, keep cooking them another three to four minutes after the shells open. Discard any that don’t open;
  • If you’re cooking shucked oysters, boil or simmer them for at least three minutes, or until the edges curl;
  • Fry shucked oysters at 375 degrees for at least three minutes;
  • Broil shucked oysters 3 inches away from the heat for three minutes;
  • Bake shucked oysters at 450 degrees for 10 minutes; and
  • Barbecuing oysters just until they open will not kill vibrio bacteria, so keep them on the grill for several more minutes after they open.

Shucked oysters should keep in the refrigerator for up to two days and in a freezer for up to three months.

Here’s to safe eating
Don’t forget proper food handling techniques.

The following suggestions from the Washington State Department of Health will help you handle and prepare shellfish and other seafood safely.

Before starting food preparation, be sure that the preparation area and all surfaces, utensils, pots, containers, and serving dishes are clean. your hands thoroughly with soap and warm water before preparing food or working with new foods or utensils and after finishing food preparation, handling raw meat or poultry, using the bathroom, changing diapers, petting animals, coughing or sneezing into your hands, blowing your nose, smoking, eating or taking out the garbage.

Don’t let juices from raw seafood, meat or poultry come into contact with each other or with other foods, especially cooked or ready-to-eat ones like lettuce, fresh fruits, or lunch meats.

Wash cutting boards, utensils, counters, sinks, and hands with hot, soapy water after preparing raw seafood, meat, or poultry

Keep your fingernails clean, and use clean dishwashing cloths and towels. Better yet, use disposable materials like paper towels for cleaning, and don’t reuse them.

Use plastic cutting boards instead of wooden ones, which are porous and more difficult to keep clean. Replace plastic boards with deep cuts in which bacteria can accumulate.

Don’t taste seafood, meat, poultry, or eggs when they are raw or during cooking.

Serve cooked shellfish on a clean plate, never the same, unwashed plate that was used to hold raw product.

Ah, shucks — how do you get those shells open?

Click here to watch a short video about how to shuck oysters like a pro.

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