Canned tuna is a popular pantry staple around the world. It’s affordable, nutritious, and convenient. But what if you discover a can past its “best by” or expiration date in the back of your pantry? Is it still safe to eat?
The short answer is that canned tuna can usually be safely eaten after its “best by” or expiration date, provided the can is in good condition and has been properly stored. However, the taste, texture, and nutritional value may slowly degrade over time.
This article examines in detail the safety and quality of expired canned tuna and provides tips on identifying when a can of tuna has truly gone bad. With some common sense precautions, eating slightly expired canned tuna poses a very low risk. But as with all preserved foods, don’t go too far past the expiration date.
What Do Expiration Dates on Canned Tuna Mean?
Let’s start by reviewing what those stamped numbers on canned tuna actually mean. There are two main dates to look for:
Sell By or Best Before Date: This date indicates when the canned tuna will be at peak freshness and quality. The product should still be safe to eat for a reasonable time past this date, but its flavor and texture may slowly start declining.
Use By or Expiration Date: This is the last date recommended for consumption. The product should still be safe after this date but may not taste as good. It’s best to eat the tuna before this date has passed.
So in summary, “sell by” and “best by” dates are about quality, while “use by” and “expiration” dates are about safety. With unopened shelf-stable foods like canned tuna, the expiration timeline past its best by date is usually quite long.
How Long Does Canned Tuna Last After the Expiration Date?
Properly stored canned tuna has a reasonably long shelf life of 3-5 years from the manufacturing date printed on the can. This shelf life extends well beyond the 1-3 year “best by” dates typically stamped on canned tuna.
If the can has no visible rust, bulging, or cracks after its sell by date, the tuna inside should be safe eat for the following times:
1-2 years past its sell by date: Quality slowly declines but tuna is likely still nutritious and safe if the can is in good condition.
3-5 years past its sell by date: Quality degraded but tuna is probably still safe if stored properly. Eat soon and inspect can closely before opening.
5+ years past its sell by date: Quality very degraded. Safety becomes a larger concern due to loss of nutrients and potential spoilage. Inspect can extremely closely before opening.
Does High Acid Content Help Preserve Canned Tuna?
Yes, the high acidity of canned tuna helps it keep longer than lower-acid canned foods. Canned tuna is packed in water or oil that has added salt, seasoning, and often citric acid or vinegar. This extra acidity inhibits bacterial growth and helps prolong shelf life.
Other high acid canned foods like tomatoes also keep for several years due to their natural acidity. Lower acid canned foods like vegetables don’t last as long beyond their expiration dates.
How to Store Canned Tuna for Maximum Freshness
Proper storage is key to maximize the shelf life of canned tuna once opened or after its best by date. Follow these storage guidelines:
- Store unopened cans in a cool, dry place like a pantry or cupboard – avoid warm, humid areas like by a oven or dishwasher.
- Avoid storing cans directly on concrete floors which can transfer dampness.
- Rotate stock and use oldest cans first.
- Once opened, transfer tuna to an airtight container and refrigerate. Use within 3-4 days.
- Don’t freeze opened canned tuna – freezing denatures proteins and makes the texture mushy.
- Look for visible rust, bulges, leaks, cracks or deeply dented seams before opening old cans.
- Never eat from a can with a hiss or spurting liquid when opened – may indicate Clostridium botulinum bacteria.
- Avoid extreme temperature fluctuations which accelerate food deterioration.
How to Tell If Expired Canned Tuna Is Safe to Eat
Follow your senses of sight, smell and touch to determine if that can of expired tuna seems OK:
Inspect the Can’s Condition
Check for these signs of deterioration before opening:
- Rust: Surface rust is harmless but deep or pitted rust could allow bacteria inside the can.
- Dents: Slight dents on top or bottom are OK but deep sharp dents along the seams may compromise the seal.
- Bulges: Bulging ends indicate gas production and spoiled contents.
- Cracks along seams also compromise the can’s seal and allow microbes inside.
- Leaks show an unsealed can – never eat leaked canned food.
A damaged can often has visible warning signs. When in doubt, play it safe and discard any suspicious looking cans.
Smell Test
Once opened, expired canned tuna should not smell sour, sulfurous or have an ammonia-like odor – discard it. Good tuna has a mild briny scent.
Rancid tuna gives off distinctive bad odors from decomposition. If it passes the smell test, proceed to the visual inspection.
Look for Color Changes
Fresh tuna is pinkish-beige. Off-color changes may indicate spoilage:
- Brownish or yellow – oxidation
- Grayish – microbial spoilage
- Cloudy whitish liquid – protein coagulation
- Soft white lumps – calcium lactate crystals (harmless but undesirable texture)
Texture & Flakes
Expired but still safe canned tuna will be relatively firm and flaky. Discard mushy or gelatinous tuna with an abnormal translucent appearance.
Taste Test
Spoiled tuna tastes unpleasantly sour, bitter, rancid or vinegary. Edible but degraded quality tuna may taste flat, bland or metallic.
If the tuna smells fine but tastes a bit “off”, it’s still probably safe to eat but of lower nutritional quality. Flavor declines faster than safety with expired canned foods.
Potential Health Risks of Spoiled Canned Tuna
Eating spoiled canned tuna comes with some health hazards:
- Foodborne Illness – Bacteria like Staphylococcus aureus, Salmonella, Listeria or Clostridium botulinum from opened cans can cause food poisoning symptoms.
- Scombroid Poisoning – Improperly refrigerated tuna may harbor high histamine levels, triggering allergy-like reaction.
- Mercury Poisoning – Outdated tuna may have increased mercury levels from decomposition.
- Nutrient Loss – Vitamins like B12, B6, C, D, and minerals degrade over time.
- No Nutritional Value – Severely spoiled tuna provides no energy or nutrients if safety enzymes have broken down.
Pregnant women, elderly, infants and those with compromised immunity are most at risk from contaminated spoiled foods. Healthy adults usually only suffer temporary digestive distress from eating small amounts of degraded canned tuna.
Tips for Safely Consuming Expired Canned Tuna
To maximize safety and quality when eating potentially expired canned tuna:
- Inspect the can closely and open carefully before use. Never eat from a leaking, bulging or deeply dented can.
- Remove tuna from the can and inspect thoroughly before eating. Check for off-colors, odors, mushy texture.
- Cook expired canned tuna thoroughly to 165°F minimum internal temperature to kill any bacteria present.
- Don’t eat excessive amounts of outdated tuna over a short period – vary your proteins.
- Consume extra virgin olive oil, tomatoes, citrus fruits or lemon juice to mask metallic flavors.
- Avoid serving outdated tuna to those most vulnerable – infants, elderly, pregnant women, and immunocompromised.
- Store open cans in the refrigerator and consume within 3-4 days – don’t freeze.
With some caution, eating expired canned tuna poses a low risk for most healthy people. But use common sense when evaluating each can’s safety and quality.
Frequently Asked Questions
Here are answers to some common questions on eating expired canned tuna:
How long does tuna last in the can once opened?
Refrigerate opened canned tuna within 2 hours and use within 3-4 days. Discard any uneaten portion as the quality quickly declines. Don’t freeze as tuna becomes mushy when thawed.
Can I eat canned tuna that expired 2 years ago?
It’s likely safe if the can has no rust and was stored in a cool, dry pantry. Inspect carefully before eating. Flavor and nutrition may be diminished. Discard if smell, color or texture seem off.
What happens if you eat spoiled canned tuna?
Symptoms like nausea, vomiting, abdominal cramps, headache, fever or diarrhea may occur within 12-36 hours of consumption. The severity depends on your health, the tuna’s condition and amount consumed.
Can expired canned tuna make dogs or cats sick?
Yes, dogs and cats can also suffer food poisoning or parasitic infections if fed spoiled tuna. Stick to tuna that is still within date and properly stored.
Is it better to freeze or can tuna for longer shelf life?
Canning preserves tuna longer than freezing. Commercially canned tuna keeps 2-5 years. Frozen tuna should be eaten within 3-6 months before taste and texture decline.
The Bottom Line
The bottom line is that canned tuna can usually be safely eaten within several years of its printed expiration date if the can is in good condition and has been properly stored.
However, its quality, taste, and nutritional value slowly deteriorate over time. While out of date canned tuna might be safe, its not as tasty or nutritious.
Inspect cans closely and use your senses before eating long expired tuna. If in doubt, play it safe and discard any cans that show signs of damage, leakage or spoilage.
With some common sense, eating canned tuna a few years past its expiration poses a very low safety risk for most people. But remember that shelf life varies based on how it was handled and stored.
