While eating freezer-burned food won't hurt you, it will definitely leave a bad taste in your mouth. Freezer burn has nothing to do with food safety, but unfortunately, it adversely affects quality. Rescue lightly freezer-burned tuna steaks by removing the afflicted areas of meat before cooking as usual.
Identifying Freezer Burn
Freezer burn on tuna steaks and other meats presents itself in the form of grayish-brown leathery patches. Caused by oxidation, or the contact of oxygen on the surface of the fish, freezer burn leaves fish and other meats with a tough texture and altered flavor. Cut any areas of freezer burn off of a tuna steak before cooking for the best results. In cases of extensive freezer burn covering large areas of the tuna steak, discard the entire steak.
Frozen Fish Best Practices
Always thaw frozen tuna steaks in the refrigerator -- not on the counter. For quicker thawing, use a microwave's defrost setting or immerse the tuna steak in cold water, changing the water frequently until the tuna is thawed. Once a freezer-burned tuna steak is pliable, inspect it further for quality. Smell it before cooking, as fish that has been freezer burned often develops a rancid smell, rendering them of poor quality for cooking. If the now-fresh tuna steak smells bad, discard it without cooking.
Preventing Freezer Burn
Prevent freezer burn by properly packaging tuna and other meats for freezing. Always use a freezer-safe bag or container when freezing tuna steaks. Wrapping tuna steaks in more than one layer of plastic wrap or aluminum foil and then sealing them in freezer-safe bags is effective to extend the freezer life of tuna steaks and other frozen foods. If you freeze a lot of seafood and meat, use an airtight, vacuum-sealing storage sealing system to better package items and prevent freezer burn.
Outside of packaging, the easiest way to avoid freezer burn is to simply eat tuna steaks within the recommended time frame before freezer burn has a chance to occur. Freeze tuna steaks for up to 3 months for the best quality. This recommendation is for quality only -- frozen foods remain safe indefinitely if continuously frozen at 0 degrees Fahrenheit, but they won't necessarily be tasty forever. Because tuna is a fatty fish, storing it beyond the recommended length will result in a loss of quality quicker than many other meats.