Here's How You Should Really Be Storing Tuna

Generally speaking, canned meat isn't known for being all that great. Corned beef in a can is never as good as the fresh kind, SPAM is loaded with sodium and fat, and so on. Then there's canned chicken, which has a reputation of being so detestable, it was once a mystery basket ingredient on "Chopped" (via YouTube). Canned tuna, on the other hand, is not only tasty despite coming from a can, but it's also convenient and versatile.

Canned tuna, like every other canned food, has an impressively long shelf life, but it does have to be stored properly for optimal freshness. (It is still fish, after all.) According to the National Fisheries Institute, tuna in cans and pouches must be stored off the floor in a cool environment, ideally at room temperature. If you follow these guidelines, you shouldn't have any issues with the quality of your tuna. However, the National Fisheries Institute notes that if you notice the can is bulging at the top or if the pouch is slightly puffed out, this is a clear indicator that the tuna inside has gone bad and should be discarded.

How long should you keep tuna?

While tuna can last for years in a can, once you open the container, that expiration date is no longer relevant. As The Spruce Eats explains, it's the vacuum seal of the can or pouch in question that does the preserving, not any chemical additives or preservatives in the tuna itself. Canned tuna, in addition to the actual fish inside, only contains water or oil. Therefore, when it's been opened, the tuna should be treated like any other cooked tuna — that is, it should be refrigerated, sealed, and used within four days. 

However, please note that the storage timeline for fresh, raw tuna is much less flexible. Fresh tuna should actually be used the same day you purchase it. Otherwise, it must be placed in the freezer immediately, after which it's good for only another 24 hours. Fortunately, there is a way to store fresh tuna for up to three months, but that includes sealing the tuna in an airtight bag along with a solution of ascorbic acid, water, and salt. Of course, if that sounds like a little too much effort, meal planning, and investment into vacuum-sealing equipment, there's always canned tuna.