Canned Tuna FAQ

Canned Tuna FAQ: Questions and Answers

Here are the answers to some of the most frequently asked questions about canned tuna.

Question: What is the shelf life of canned tuna?

Answer: Canned tuna is quite stable and has a long shelf life compared to other canned seafood products.  The best way to find the actual shelf life of your canned tuna is to check on the can label and determine the manufactures recommended shelf life.  Typically this will be about 3 years.  However, if the tuna can is stored in a dry pantry or shelf this can be increased by a few years.  Of course you must make sure that the can has not been damaged or broken in any way and there are no air openings. See below for storage of canned tuna once opened.

Q: Can canned tuna be stored after it has been opened?

A: Once your canned tuna has been opened it must be kept in a refrigerator if you did not eat all of it.  If wrapped properly and stored in your fridge it should last for around three days.  If you want to increase this time period you could put the tuna in a freezer bag and store it in the freezer for later consumption within a few months.  As with any seafood products you must not leave your canned tuna for an extended time period at room temperature.

Q: Can I feed canned tuna to my cat? Can I feed canned tuna to my dog?

A: Canned tuna is a product that is made for consumption by humans and is therefore not specifically recommended to be fed regularly to pets.  As dogs and cats are typically smaller and have different diet needs than humans the allowable additive and product regulations developed by U.S. and Canadian Food bureaucrats do not apply.  An example is the amount of mercury present in canned tuna.  However in most cases it should be okay to feed canned tuna to your cat or dog every so often.  If you choose to feed canned tuna to your cat or dog it is best to buy no-salt added canned tuna in order to keep the sodium level down.

Q: How can I tell where the tuna is caught?

A: Most food regulations mandate that the label must state where the tuna was sourced from.  Check the can label and if it does not indicate where your tuna is from then be very wary about that product.  We would not recommend purchasing any canned tuna product that does not indicate the source.

Q: How do I tell if my canned tuna is from a sustainable source or fishery?

A:  The best indication of the source and fishing methods used to catch the tuna is found on the can.  In most cases a company that employs sustainable fishing practices will disclose how the tuna is caught on the can itself.  A good brand should disclose the species of tuna, where the tuna is from and the fishing method used. For example: ‘Pole and Line Caught Skipjack Tuna from

Marine Stewardship Council (MSC) certification logo

California;.  If the only information you can find on a can of tuna is a word saying “Tuna” then you should probably avoid this brand as you can be fairly sure it is from an unsustainable source.  Many companies may also have sustainability principles built into their brand and buying seafood from these brands helps ensure you are buying sustainably caught tuna.

There are also many different types of certifications that a fishery may get to show that they are using sustainable fishing methods.  It is important to know these labels and what they stand for in order to have a good understanding of how the tuna was caught.  A good example is looking for tuna with the Marine Stewardship Council -MSC logo (shown on right). Click here for more information on MSC Tuna.

Q: What is dolphin safe tuna

A: The dolphin safe logo is used to show tuna that was caught without killing dolphins.  Many tuna fisheries now employ dolphin friendly fishing techniques to minimize or eliminate dolphin bycatch kills.  However, some fisheries are now using FAD’s (fish aggregation devices) to attract tuna which, while minimizing dolphin kills, have added to the deaths of other species such as turtles and sharks.  Check out our page on dolphin safe tuna for more information.

Q: Why does canned tuna have mercury in it?

A: Mercury is present in many different species of animals.  However as a species moves up the food chain the mercury levels increase as they consume the smaller animals that also contain mercury.  Because tuna is a large predator species of fish it will have a higher concentration of mercury than smaller fish. For a better explanation of why mercury is present in tuna click here.

Q: Where can I buy canned tuna?

A: Most grocery stores in Canada and the United States have canned tuna for sale.  In addition many websites sell canned tuna online.  If you want to purchase canned tuna, either Skipjack Tuna, Albacore Tuna or no-salt added canned tuna then check out the buy canned tuna online page of our site.