Things You'll Need
Zip-top plastic freezer bag
You can extend the shelf life of canned tuna by repackaging the fish for storage in the freezer. Canned tuna is cooked all the way through during the canning process to preserve it for up to three years while the can stays sealed. Once the seal on a can of tuna has been opened it must be kept cold to avoid spoilage. Canned tuna that has been properly frozen will keep for as long as three months before it begins to degrade in flavor and texture.
Remove the lid completely from the tuna can. Use a can opener or pull the can all the way off it it's a ring-top can.
Pour the canned tuna into a quart sized zip-top plastic freezer bag and gently squeeze out all the excess air before sealing the bag securely.
Write the words "expiration date" and record a date that is three months in the future on the front of the freezer bag.
Place the bag into a freezer that maintains a constant temperature of 0 degrees Fahrenheit or below at all times.
Thaw the frozen canned tuna by moving the freezer bag into the refrigerator for one to two days until it has fully defrosted. Keep open cans of tuna in the fridge for up to two days until you decide whether to use the fish or freeze it. Clean all surfaces that come in contact with the tuna or any of the liquid from the can with hot, soapy water to prevent foodborne illnesses.