Canned tuna is one of those pantry staples you never really think about. You grab a few cans at the store, they sit in the cabinet for months, and one random weeknight you crack one open for a sandwich or a quick bowl of pasta. Most of the time, no problem. Americans go through roughly one billion pounds of the stuff every year, which makes it the second most popular seafood product in the country. But shelf-stable does not mean it lasts forever. A can can go bad, and there are a few dead giveaways that should make you stop mid-bite and toss it.
If the Can Is Bulging, Don’t Even Open It
This is the big one. If you pull a can out of the cabinet and the top or bottom is puffed up like a tiny dome, put it straight in the trash. A bulging can usually means bacteria inside are producing gas, and that gas has nowhere to escape. It is the single most reliable warning that something has gone wrong in there. Do not open it to “check,” do not taste a bit, do not try to save the tuna for the cat. Just get rid of it. A good can should sit flat on the top and bottom, maybe with a little give when you press it, but it should never look rounded out.
Dents, Rust, and Leaks Mean the Seal Is Gone
The whole point of a can is the airtight seal. Once that seal breaks, oxygen and moisture sneak in and the tuna is no longer protected. Rust on the outside is a hint that air and water may have already found a way inside. Leaks are an automatic no. If there is any liquid seeping out, even a small crusty spot around the rim, that can is done. And pay close attention to dents on the lid. Grocery stores love to knock a few cents off dented cans, and a small ding on the side is usually harmless. But a dent right on the top or along the seam can pop the seal without you ever noticing. That is the one to skip, even at a markdown.
Give It the Sniff Test
Canned tuna is not supposed to smell like a bouquet of flowers. A little fishy, a little metallic, that is normal and expected. What you are watching for is the sharp stuff. Spoiled tuna hits you with a sour, acidic, almost rancid punch the second you peel back the lid. Think of the smell of something that clearly turned. If your nose recoils, trust it. That reaction is older and smarter than any date stamped on the bottom, and it is one of the easiest ways to catch a bad can before it lands on your plate.
Watch the Color and Texture
Good canned tuna has a consistent look. Light tuna runs pale tan, albacore is closer to a clean off-white or pale pink, and the flakes should hold together when you drag a fork through them. When it goes off, that changes. Look for dull, muddy, grayish coloring instead of a clean flake. Dark brown or black streaks running through the meat are a bad sign. So is a slimy or mushy texture, or a sticky film on the surface. If you scoop it out and it looks like a sad, watery paste with weird dark lines, that can either sat too long or something got inside. Don’t gamble on it.
Remember, There Are No Preservatives in There
Here is something a lot of people get wrong. Canned tuna is not loaded with preservatives. It is simply cooked and packed in water or oil, then sealed. That is it. The can itself is doing all the work of keeping the tuna good. So when the packaging fails, there is no chemical safety net picking up the slack. That is exactly why a compromised can matters so much more with tuna than you might assume, and why a puffed lid or a leak is a bigger deal than a scuffed label. The airtight seal is the whole system.
Opened Tuna Has a Short Clock
People treat an open can like it can hang out in the fridge all week. It cannot. Once you open it, tuna is good for about three to four days in the refrigerator, and that is only if you store it right. Do not leave it sitting in the open can. The metal can throw off a tinny taste and speed things along. Scoop the leftovers into a small airtight container, glass if you have it, and push it toward the back of the fridge where the temperature stays steadiest. Keep the fridge at or below 40 degrees. Label the container with the date if you are forgetful, because after four days it goes in the trash no matter how fine it looks.
The Best-By Date Is Not an Expiration Date
Here is another thing that trips people up. That stamped date on the bottom of the can is a best by date, not a hard cutoff. Unlike milk or fresh meat, an unopened can of tuna has no true expiration date. Stored in a cool, dark spot, it can stay good for two to five years, and plenty of cans are perfectly fine past the printed date. The date is about peak quality, not a shutoff switch. That said, flavor and texture do slowly slide over time, so a can you dug out of the back of the pantry from three moves ago might taste flat even if nothing is technically wrong with it. Inspect it, sniff it, and use the signs above before you commit.
The Genova Recall You Should Actually Check For
Now for the one case where the “looks fine, smells fine” rule goes right out the window. In January 2026, the FDA flagged canned tuna that had quietly landed back on shelves across nine states. Tri-Union Seafoods had pulled these cans earlier over a defect in the easy-open pull-tab lids that could break the seal over time, and a third-party distributor accidentally released product that was supposed to stay quarantined.
The recalled products are Genova Yellowfin Tuna in Olive Oil (5.0 oz, sold in a 4-pack, UPC 4800073265) with can codes S84N D2L or S84N D3L, and Genova Yellowfin Tuna in Extra Virgin Olive Oil with Sea Salt (5.0 oz, UPC 4800013275) with code S88N D1M. Check the bottom of the can for those codes. The affected cans went to Meijer stores in Illinois, Indiana, Kentucky, Michigan, Ohio, and Wisconsin; Giant Foods in Maryland and Virginia; and Safeway, Albertsons, Vons, and Pavilions in California.
The key part: officials say do not eat this tuna even if it looks and smells completely normal. If you have a can that matches, you have three choices. Return it to the store for a full refund, throw it away, or call Tri-Union Seafoods at 833-374-0171 for a retrieval kit and a coupon for a replacement. No illnesses had been reported when the alert went out, and that is exactly the point. The goal is to catch it before anything happens.
When In Doubt, Toss It
The theme running through all of this is simple. Canned tuna is cheap, and your peace of mind is worth a lot more than the buck or two you save by finishing off a questionable can. If the can is puffed up, rusty, leaking, or dented on the lid, do not open it. If it smells sour, looks muddy, or feels slimy, do not eat it. If it is one of the recalled Genova cans, leave it alone no matter how normal it seems. A few people even notice a peppery or tingling feeling on the tongue with the first bite of tuna that is off, and that is your cue to put the fork down right away. With seafood, the old rule holds up better than ever. When in doubt, throw it out.
