Shellfish like clams, oysters and mussels are a delicious appetizer or main course for everyday eating or a special occasion. If you’re planning a meal with shellfish make sure you know exactly how to keep it properly stored for optimal freshness, flavor and safe enjoyment once it’s ready to eat! In this article we’ll review exactly how to keep your clams, oysters and mussels preserved and some best practices for determining whether they’re still good to eat. 

How Long Does Shellfish Stay Fresh?

Experts often recommend eating shellfish the same day that it is purchased or delivered. However, for many reasons this is not always possible, including if you have purchased shellfish for a future event. Fortunately, shellfish can be kept fresh for varying periods of time. Typically, shellfish can be kept stored safely and enjoyed for at least several days or up to 2 weeks, depending on whether it’s a clam, oyster or mussel and how well it’s preserved. 

How to Keep Oysters Fresh

If you’re planning to serve your oysters even a week or so after they’re purchased, make sure to store them properly to preserve their freshness and flavor. There are some simple answers to the question of how to keep oysters fresh before being eaten. 

Firstly, only oysters that are still alive can be kept fresh. Dead oysters (i.e., those that have been opened, exposing the organs and liquor to air) cannot be preserved more than a few hours before they need to be eaten. Oysters that have not been shucked - which is the process where each half of the mollusk is separated - can be kept fresh for up to 2 weeks if they were recently harvested and are stored properly.

Learning how to keep oysters fresh is actually pretty simple and relies on two primary factors: keeping the oysters cold and limiting their exposure to air. Remember that the natural environment for an oyster allows them to “breathe” in their salt water habitats. Once oysters are removed from salt water they stop breathing and their shells will remain closed until they are shucked.

Here are a list of tips for exactly how to keep oysters fresh for enjoyment well after they are purchased:

• Keep oysters in a light bag (they will likely be in a plastic bag when purchased online or from in a store). 
• Place them in a bowl or pan and cover with a damp cloth.
• Keep in a fridge.
• Unbagged oysters can be kept on ice as long as the freshwater has a place to drain. For example, oysters can be kept on ice in a colander, steam pan, or any other type of storage that will not hold the melted ice water. 

For more tips and info on how to shuck, prepare and understand the different oyster varieties, read our full article here.

How to Keep Clams Fresh

While clams can be preserved for a short time, it’s unfortunately not nearly as long as oysters. In fact, clams might have the briefest preservation period of any shellfish and often need to be eaten within 48 hours. Follow the full list of recommendations below to answer any questions you have about how to keep clams fresh.

• Clams also need to breathe to stay alive, which means that they can be exposed to open air. Keep your clams loose and unbagged in a bowl or pan. 
• Cover the clams with a damp towel.
• Store them in the fridge and eat within 1-2 days. 

How to Keep Mussels Fresh

Mussels can be kept fresh for up to 5 days depending on how they were harvested and if they are shipped before consumption. However, we recommend eating them within 1-2 days after they arrive or are purchased. Here are some quick tips on how to keep mussels fresh if you’re planning a meal with these scrumptious shellfish in the near future.

• Place the mussels in an open container to allow for air flow.
• Cover the mussels with a damp cloth.
• Store the container of mussels in a refrigerator and eat within 1-2 days. 

How to Tell if Shellfish Has Gone Bad

There are a few indications to help you determine if shellfish have gone bad, including if the internal muscles and organs appear gray and smell rotted. Fresh shellfish often smells like the ocean; not putrid or sour. A strong ammonia smell is a reliable sign that the shellfish have spoiled. Because rotten shellfish can cause serious illnesses when consumed, a good rule of thumb is to dispose of any shellfish that has signs of decomposition or rot. 

General best practices for keeping your shellfish fresh include:

• Don’t open (shuck) them unless they are going to be eaten.
• Don’t store them at room temperature.
• Don’t store them directly on ice (unless they have been shucked for serving) without drainage.
• Don’t store them in freshwater, as they will die and spoil quickly. 
• Drain ocean water that has leaked into their storage container.
• Don’t freeze them.