Are Mussels That Float OK To Eat?

You have sourced fresh mussels from your local fishmonger or collected them yourself and started to prepare them. Paying attention to how the mussels react when you clean or cook them in water can determine whether you will get to enjoy a delicious meal or take a trip to a doctor.

Discard mussels that float in water. Floating happens when mussels are either dead, empty, or have air trapped in their shells. The latter is not problematic if the shells are still closed. In contrast, dead or empty mussels will float and have open shells. You should not eat these mussels.

There are several other ways to determine whether mussels are OK to eat, ranging from tests you can do in your kitchen to knowing what to look out for when purchasing mussels. Suppose you find yourself in the predicament of having already consumed a bad (dead) mussel. In that case, it is also worth noting the physical symptoms you might experience to confirm that the culprit is, in fact, a mussel.

How To Test Whether A Mussel Is Safe To Eat

One way to test the freshness of your mussels, is to place them in water and to see if they float, in which case you should discard them. A side note to this method is that mussels can die in tap water if they are left submerged for longer than 15-20 minutes, so keep track of the time when applying this method.

A way to test the freshness of an uncooked mussel that is partially open is to squeeze the mussel shut. If the mussel stays closed, then it is safe to eat. If the mussel opens again, you should throw it out.

You can also give raw open mussels a tap with a knife, the back of a spoon, or even on a countertop. If they do not close, you should discard them since this is a sign that the mussels are dead.

If you have proceeded with cooking your mussels (approximately 3-5 minutes), the easiest way to test whether they are safe is to check which mussels are still closed. People have differing opinions over whether you could still eat these closed mussels but rather discard them to be safe.

What Happens When You Eat Bad Mussels?

The meat of dead mussels deteriorates very quickly and is prone to contamination by bacteria and viruses. The results of eating dead mussels can thus cause food poisoning, and the first signs could appear anytime between 30 minutes and 2 hours after consumption.

Food poisoning from mussels and other shellfish will expose itself through the following symptoms:

The most effective way to treat food poisoning is by managing the symptoms. You need to make sure that you stay well hydrated by drinking lots of water and try to avoid vomiting if possible. It would also help if you abstained from taking medication that controls diarrhea, vomiting, and stomach cramps. The medicine might prolong your state because your body cannot quickly get rid of the infectious agent.

Things To Consider When Buying Mussels

You can safely buy fresh and frozen mussels year-round, but peak season is during the winter months or in months with the letter “R” (October to March), as commonly believed. During these colder months, the taste and quality of the mussels are at their best, just before they begin spawning in the spring and summer.

Another reason mussels harvested in winter are considered safer is because Red Tide often occurs during the summer months. Red Tide happens when algae grow and reproduce at such a rapid rate that it causes a toxic buildup of organisms in the ocean. If you consume mussels or any other shellfish that have absorbed the toxins released in the water during Red Tide, you can get shellfish poisoning.

No matter the time of year, when buying fresh or frozen mussels, it is essential to use your senses. Avoid mussels with chipped, broken, or damaged shells. Instead, look for mussels that are tightly closed. Fresh mussels will also smell like the sea: Salty and fresh. Do not buy mussels that smell overly fishy or like sewage.

How Long Can You Keep Mussels Before They Go Off?

It is best to prepare and cook fresh mussels as soon as possible after buying them or at least on the same day. They will, however, keep in a 1°-to-4°-degree fridge overnight for up to 24 hours.

If you want to store mussels in the fridge for a day or two, you must put them in a dry bowl or container covered with a damp cloth. Do not store the mussels submerged in water because they will die. You can place them on ice, but only if the water can drain away. Covering the container with cling wrap or an airtight lid is also not advisable because the mussels will suffocate.

If you need to store mussels for longer than a few days, you can freeze them in freezer-safe bags. Fresh, uncooked mussels will keep in the freezer for up to three months, while cooked mussels can last for six months before they go off. 

How To Test Whether Shellfish Is OK To Eat

Some tests to determine the freshness of mussels can also apply to other shellfish. For example, clams that float in water are considered dead and are thus not OK to eat.

Open clams and oysters can also be tested by gently tapping their shells. If the shells close, then it is safe to consume. If they do not respond and remain open, you should throw them out.

Like mussels, scallops that are alive will also have a fresh sea odor which means they are safe to eat. If scallops smell overly fishy, you should discard them. 

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Using your senses is key to determining whether mussels are OK to eat. Notice the physical signs: floaters and mussels with damaged or permanently open shells are signs that they are bad (dead), so discard them immediately. On the other hand, cooked mussels should be open before eating them. Also, ensure that your raw mussels have a fresh, sea air smell before you buy them.

Another precaution you can take to avoid bad mussels is considering the time of year. Ideally, it would be best if you consumed mussels that have been fished or harvested during the winter months. If you are unsure, do not be afraid to ask your fishmonger when buying or even the chef at a restaurant if you are ordering a mussel dish. They should be able to confirm the freshness of the mussels.