How To Immediately Tell That Your Tuna Steaks Are Not The Freshest - Tasting Table
Briefly

When selecting the best tuna steak, look out for ones with a uniform red or pink color and a moist, slightly sticky texture.
It takes a little more to indicate that the fish is completely bad, such as changing color or developing a fishy smell.
A bit of flaking means tuna isn't the freshest, but unless there are signs like a foul smell or slime, it's not completely spoiled.
To maintain freshness, if you can't cook the raw tuna soon after purchasing, wrapping it and freezing it is a good precaution.
Read at Tasting Table
[
|
]