A co-worker and I are having a disagreement on whether or not it's okay to put unopened cans of pizza sauce in a refrigerator. I say it's not, because the acidity in the tomatoes in the can will make someone extremely ill. He thinks as long as it is not opened, it will be fine. Who is correct?

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    The tomatoes have the same acidity whether they are in the refrigerator or not. You seem to essentially be asking whether canned tomatoes are safe.
    – SourDoh
    Feb 7, 2014 at 16:11
  • 4
    Just curious: Why would you put unopened cans in the fridge?
    – Mien
    Feb 7, 2014 at 16:13
  • Cans tend to work there way to the front, where they'll fall out, and hit you on the toe. Other than that, and the remote possibilty the fridge is set too low and will freeze the cans, distortiong their shape, there should be no danger. May 5, 2015 at 8:11
  • @mien The same reason you put anything else in a fridge - to reduce their temperature. Some dishes are better served chilled, and chilling cans in advance is more efficient.
    – JBentley
    Feb 9, 2016 at 17:49
  • @JBentley Certainly true in general, but the OP did ask about pizza sauce.
    – Cascabel
    Feb 21, 2016 at 17:18

5 Answers 5


There's nothing wrong with storing unopened metal cans in the refrigerator. But it's pointless in terms of food safety - the whole point of canning is to make the food safe to store at room temperature. Don't waste the fridge space unless you're actually trying to chill the contents of the cans.

Now, if the cans are open, sure, that's a problem. You should transfer the food to a sealed container for storage, whether it came from a can or a pot or anywhere else.

But none of this has anything to do with acidity. Acidity doesn't make you sick, and in fact, it can help keep bacteria from growing and keep food safer. That's why a lot of canned goods have a bit of acid added, and why we pickle foods.

  • I wouldn't always say it's pointless to store unopened cans in the fridge because it extends the shelf life considerably. But the shelf life is already long enough at room temperature for most people. So it's only pointless most of the time. Even when it's not pointless, it's probably not worth wasting valuable fridge space on it. So, yeah, it's pretty much the same thing as pointless. :-)
    – mrog
    Jan 10, 2016 at 5:51
  • You provided a good reason for refridgerating a can right after saying it's pointless! Good answer otherwise.
    – JBentley
    Feb 9, 2016 at 17:51
  • @JBentley It's possibly a good reason to put them in the fridge a bit before use, but it's not really a good reason to store them there (i.e. long term) and doesn't have much to do with the question of safety.
    – Cascabel
    Feb 9, 2016 at 18:05
  • I ended up here as the result of a search.. I want to put unopened cans of fruit cocktail in the fridge because I don't like warm fruit in my cold cottage cheese. It's not "POINTLESS" just because you don't get it.
    – user43580
    Feb 21, 2016 at 15:54
  • @DougGann Please read the whole answer (which I've edited to make even clearer). I'm not saying that cold food is pointless. I'm saying that chilling an unopened can doesn't have any safety effect. Note that the OP was asking about pizza sauce, which I'm pretty sure they weren't trying to eat cold.
    – Cascabel
    Feb 21, 2016 at 16:56

I see no reason why closed cans should have a higher risk of causing the tomatoes to become acidic. When closed the only difference is, that there is no (to very little) oxygen. This is actually what causes your products to last longer. And the United States Department of Agriculture states that canned food can be stored in the fridge once opened, so it should be safe to store it in the fridge when closed.

The only difference I am aware of with closed cans is the botulism bacteria, which likes to live in anaerobic environments, where it can produce a deadly toxin. Refrigerating products usually slows down the spread of bacteria, so if anything putting the cans in the freezer helps to reduce the risk of a botulism poisoning.


Of course there's no risk. Cans are commonly stored in warehouses with no heating (and probably no control of the upper temperature limit as well) for long periods


The moisture in the fridge allows rust to start forming

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    Yes, but only on the outside. The inside is continuously moist, but la) acks the oxygen fo oxidization (=rusting) and b) should have a protective coating.
    – Stephie
    May 5, 2015 at 4:55
  • 1
    Unless it rusts all the way through, but... yeah, I don't think that's happening quickly.
    – Cascabel
    May 20, 2015 at 2:01

It is bad health and safety to put tin in a fridge. It promotes the growth of bacteria.

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    How does this apply to unopened cans?
    – SourDoh
    Feb 7, 2014 at 16:51
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    Your link refers only to opened cans. The issue is that food shouldn't be stored in open cans, not that cans can't be put in a refrigerator. The link also states that the risk is from metal leeching into the food, not bacterial growth.
    – SourDoh
    Feb 7, 2014 at 17:07
  • 5
    Yeah, this pretty much has to be bogus. Lower temperatures universally slow bacteria growth and slow all chemical reactions, including those that would cause metal to leach. I don't know why you'd want to store unopened cans in the fridge, it seems like a waste of energy, but I don't think it is dangerous. Feb 7, 2014 at 17:33
  • 2
    The question was about unopened cans of tomatoes, and your answer is about opened cans. It's completely true for opened cans, but that wasn't the question. If you have an NHS (or other authoritative reference) for why one shouldn't store unopened cans in the refrigerator, please feel free to edit your answer (or post a new one). If you don't, you're not answering the question, and we'll probably have to delete this.
    – Cascabel
    Feb 7, 2014 at 19:01
  • 4
    This claim is the unfortunate result of once-good advice that's been twisted beyond recognition and repeated throughout the media and online. Opened cans aren't safe to store in the fridge, but opened cans aren't safe to store anywhere, because of oxidation and a few other issues that refrigeration doesn't prevent. The refrigerator isn't the problem, and makes no difference whatsoever; the problem is the open-ness of the can and some people making the naïve assumption that refrigeration makes it safe. Once you open a can, you should transfer leftovers to another container - period.
    – Aaronut
    Feb 9, 2014 at 1:45

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