How to Tell If Canned Tuna is Bad? (In Four Simple Steps)

Chris Starks
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Storing Canned Tuna

Tuna is a super healthy and nutritious fish that is great in almost any form. However, canned tuna is among the healthiest ones. Canned tuna is packed with protein, and it’s also a decent source of several vitamins, including Vitamin D, Vitamin B12, Vitamin B3, and of course, Vitamin A. Just one 3 ounce can of solid chunk light tuna contains over 10 grams of protein, over 20% of your daily value of Vitamin D, and over 10% of your daily value of Vitamin B12. In fact, solid chunk light tuna is one of the best seafood sources of Vitamin D.

How to Tell if Your Canned Tuna is Bad

Each year, Americans consume more than 55 million pounds of tuna. Most of us love the versatility and convenience of canned tuna, but it can be especially convenient to stock up on it when it’s on sale or when you’re at the store and it’s the only food in the cupboard. The problem, though, is that cans of tuna have an extremely long shelf life … so long that it may be months before you turn them into a meal or two. That’s a long time for tuna to sit in your pantry and go bad, and it’s even longer since you may not notice that the tuna is bad if its seal is still intact.

Here are four easy steps to help you troubleshoot whether it’s okay to eat the tuna you have on hand.

Check the Expiration Date

Step 1 – Consider the Date on The Can

We all like to think that the canned tuna sitting on grocery store shelves has an expiration date that’s long past, but sometimes you might find a can on the shelf that’s the last one (or maybe only one) that’s in stock. You can consider this unique situation an exception, but only if it satisfies the following conditions.

If the can is less than six months old, it’s fine to buy it and eat it. If it’s more than three years old, throw it away.

The next time you’re at the supermarket, pick up a can of tuna, check it, and if the date is anywhere between the 3 to 6-month range, go ahead and buy it. However, if the date just doesn’t appear anywhere on the can, you’ll have to take the second step, where we’ll look at the can’s structure.

Step 2 – Consider the Quality of The Tuna Can

Next, in our tuna test comes the quality of the tuna can. Most tuna cans have a quality printing or sticker that contains expiration date. Now, how do you know if your tuna is bad by its can? Pull out the expiration date on the tuna’s can. The date on the can tells you how long tuna is good for and if it’s still safe to eat.

If you tuna can has a wide open space between the expiration date and the quality logo on the can, it means it’s still fresh. But if there is a gap between the expiration date and the quality information, it means it’s already expired. Expiration date and quality information look like a sticker. You can shake the can by holding the middle. If the lid stays firm, it means it’s still good. But if the lid moves, it might be expired.

Yes, it’s simple as that.

If your can’s quality information is loose or missing, use the smell test.

Step 3 – Open the Can

The easiest way to do this is to choose a can from the back of the shelf – in general, these cans are much older and are therefore more likely to be dated.

Look for the stamp with the printed date and open the can. Check to see how the tuna looks and smells. The best tuna should smell a little bit like the sea, like the ocean. There should be no off odors and no signs of mold or liquid.

Step 4 – The Taste Test

If you’re questioning the safety of a can of tuna, we recommend trying a taste test. That’s right. We recommend tasting a small amount to see if it’s bad.

Sure, this seems risky to some. But just as you know that the smell of rotten eggs or spoiled milk is a good indicator of something that’s wrong, you can also use your sense of smell and taste to tell if canned tuna has gone bad. What you don’t know about tuna oxidation can hurt you.

A bad can of tuna will taste unpleasant, perhaps even slightly sour. It won’t simply taste like tuna, but tuna that’s gone bad. It’s an acquired taste. Some, like me, might be able to detect the bad taste sooner than others.

Once you detect BPA from a bad can of tuna, you might be compelled to drink the rest of the can and finish it. Don’t do that. It’s bad for you. After realizing your canned tuna is bad, dispose of it properly and not eat any more of it.

In Summary

First of all, the best way by far to tell if tuna is bad, is to smell it. A bad tuna will give off a distinct, foul odor.

It will also have a thick, syrupy coating that’ll look like a dark shiny coating. The tuna meat itself will be dry and will have a dull instead of a shiny color. It will have a slimy feeling and you’ll notice a sticky texture when you touch it. Obviously, it’ll taste awful and you’ll notice a bad taste in your mouth after eating it. If you’re wondering how to tell if canned tuna is bad, start by checking the color.