Raw tuna can be safely stored for up to two days at temperatures of 39 degrees Fahrenheit or below. Refrigerated cooked tuna is safe to consume for five days after preparation. Canned tuna used in casseroles and salads will last for five days in the refrigerator.
Tuna that has been left to sit out at room temperature for more than an hour should be discarded to avoid risk of foodborne illnesses. If tuna has a foul odor or is discolored, it should not be eaten or purchased. Vibrant skin color, clear eyes and gills that are bright red in color are all indicators of healthy and fresh tuna. Packaged or canned tuna should not be consumed or purchased after the listed expiration date.