# How Long Does Cooked Food Stay Good at Room Temperature?

**URL:** <https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260>\
**Category:** Factual Questions\
**Created:** [November 1, 2000, 4:40pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260 "2000-11-01T16:40:54Z")\
**Posts on this page:** 10\
**Page:** 1

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**Author:** ![Wildest\_Bill](https://avatars.discourse-cdn.com/v4/letter/w/b9e5f3/32.png) [@Wildest\_Bill](https://boards.straightdope.com/u/Wildest_Bill)\
**Post date:** [November 1, 2000, 4:40pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/1 "2000-11-01T16:40:54Z")

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Why? You know in case you forget to put it in the fridge the night when you cooked it and you wake up real hungry in the morning but don’t want to get sick either. :eek:

For the following foods:

Steak  
Hamburger(like taco meat)or meat on a pizza)  
Shrimp  
Chicken  
Fish  
Vegetables  
Fruit  
Pizza

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**Author:** ![douglips](https://avatars.discourse-cdn.com/v4/letter/d/e68b1a/32.png) [@douglips](https://boards.straightdope.com/u/douglips)\
**Post date:** [November 1, 2000, 4:59pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/2 "2000-11-01T16:59:34Z")

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It really depends. Most of the time there won’t be anything nasty growing on your food after 8-12 hours, but you never know.

If you nuke something until it’s **really** hot, you’ll kill any nasty bacteria, and then the only thing you have to worry about is if the left some toxin behind.

I would say:  
Steak, hamburger, chicken: OK if you nuke 'em good.  
Shrimp: Raw shrimp? Toss it. Cooked shrimp? Maybe you could nuke it. I’m a bit uneasy around shellfish.  
Fish: Same as chicken, if cooked. Sushi, fuggedahboudit.  
Veggies: Nuke 'em.  
Fruit: Shouldn’t be a problem - high sugar content and all.  
Pizza: Nuke it.

You can eat your pizza cold, and you’ll probably be just fine. But, there is a small chance you got some nasty bacteria on it (botulism, anyone?) and nuking is a safeguard.

Baked goods like cakes and breads seem to not be a problem - I think you want to worry about greasy proteiny stuff like meat and cheese more than veggies, fruit, and grains.

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**Author:** ![Zenster](https://avatars.discourse-cdn.com/v4/letter/z/cdc98d/32.png) [@Zenster](https://boards.straightdope.com/u/Zenster)\
**Post date:** [November 1, 2000, 6:35pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/3 "2000-11-01T18:35:29Z")

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> [@](#):
>
> \*Originally posted by Wildest Bill \*  
> For the following foods:
> 
> Steak  
> Hamburger(like taco meat)or meat on a pizza)  
> Shrimp  
> Chicken  
> Fish  
> Vegetables  
> Fruit  
> Pizza

Let’s assume three things here:

[ol]  
[li]You have covered or wrapped all of these foods[/li]  
[li]They were completely cooked[/li]  
[li]They do not contain mayonnaise or egg products[/li][/ol]

I really do not see a problem. Mind you I have a cast iron digestive tract that is specifically trained to accept food with a mild bacteria count. Unless you have a really delicate stomach or a compromised immune system you should not have any problem either.

Try do remember that we are descended from a race of beings that went for several million years without refrigerators or tupperware. Albeit, many people intentionally sensitize themselves by sterilizing their bodies and environment with antibacterial soaps, sprays and unguents. However, the human organism is an amazingly robust structure.

Reheating (usually with a small amount of water) all of the above will help reduce any risk involved but it is fairly minimal to begin with. Even if uncovered, most of the foods you list will not pose a strict health hazard as long as they have stayed relatively cool and out of direct sunlight. An exception might be made if something had sat on a stove with pilot lights going, but that’s about it.

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**Author:** ![peace](https://avatars.discourse-cdn.com/v4/letter/p/c68b51/32.png) [@peace](https://boards.straightdope.com/u/peace)\
**Post date:** [November 1, 2000, 7:34pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/4 "2000-11-01T19:34:09Z")

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It’s a wrong qestion and cannot be answered as asked. If the correct question is “What leftover food is safe to eat” Refrigerated or not)? the answer is:  
“Spoiled food” usually means food in which microorganisms, mostly bacteria, multiplied to the degree which made it a) untasty or b) dangerous or c) both.  
if it’s only a), it’s personal  
if it’s b), short of impractical microbiological analysis, one can smell food. Most food becomes smelly before it becomes dangerous, but the danger is that, although in most cases smell would warn us, sometimes IT DOES NOT!  
Practically, all products listed by WB, except fruits and vegetables, would smell. But, again, eating them would be taking chances. You can safely eat rotten fruits and vegetables, if you can stand the taste, WB.  
In general, try to drink less, so you do not forget to put your food in the frige, again. Remember, that leftover drinks won’t spoil overnight at room temperature, food might.

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**Author:** ![toadspittle](https://avatars.discourse-cdn.com/v4/letter/t/c0e974/32.png) [@toadspittle](https://boards.straightdope.com/u/toadspittle)\
**Post date:** [November 1, 2000, 9:00pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/5 "2000-11-01T21:00:36Z")

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> [@](#):
>
> \*Originally posted by peace \*  
> \*\*Remember, that leftover drinks won’t spoil overnight at room temperature, food might. \*\*

mmmm… warm, flat beer…

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**Author:** ![Grither](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/grither/32/425_2.png) [@Grither](https://boards.straightdope.com/u/Grither)\
**Post date:** [November 1, 2000, 11:02pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/6 "2000-11-01T23:02:41Z")

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> [@](#):
>
> \*Originally posted by douglips \*  
> **But, there is a small chance you got some nasty bacteria on it (botulism, anyone?) and nuking is a safeguard.**

I was under the impression that the botulism bacteria only become “nasty” when they’re given the chance to reproduce in an environment sans oxygen (like in canned goods which haven’t been heated to a high enough temperature)

Is that true?

mm

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**Author:** ![jb\_farley](https://avatars.discourse-cdn.com/v4/letter/j/9d8465/32.png) [@jb\_farley](https://boards.straightdope.com/u/jb_farley)\
**Post date:** [November 1, 2000, 11:04pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/7 "2000-11-01T23:04:14Z")

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I enjoyed a warm, flat Yuengling Black and Tan not two hours ago.  
mmmm, just like the stupid europeans.

jb

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**Author:** ![frolix8](https://avatars.discourse-cdn.com/v4/letter/f/f04885/32.png) [@frolix8](https://boards.straightdope.com/u/frolix8)\
**Post date:** [November 1, 2000, 11:30pm UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/8 "2000-11-01T23:30:07Z")

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For the record, canned mayo is not a source of food poisoning. Canned mayo is sterile, it can sit on the shelf for a long time, and is good for 2 moths after opening if it’s kept in the fridge. Home-made mayo is a problem, as is any other food made with raw eggs.

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**Author:** ![Smeghead](https://avatars.discourse-cdn.com/v4/letter/s/f1d935/32.png) [@Smeghead](https://boards.straightdope.com/u/Smeghead)\
**Post date:** [November 2, 2000, 1:16am UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/9 "2000-11-02T01:16:18Z")

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> [@](#):
>
> \*Originally posted by douglips \*  
> \*\*If you nuke something until it’s **really** hot, you’ll kill any nasty bacteria, and then the only thing you have to worry about is if the left some toxin behind.  
> \*\*

First of all, don’t be so quick to dismiss toxin like that. Most food poisoning is entirely toxigenic. The living bacteria itself is perfectly safe - its the toxin it makes that’s a problem.

Botulism is an anaerobic organism, but it can grow aerobically. And anaerobic microenvironments can be found in food exposed to the air, so don’t think that protects you. However, C. botulinum only produces the toxin when growing on food that is slightly alkaline. Acidic food won’t give you botulism.

As for the OP, it’s hard to say. Any food that’s exposed to the environment will be colonized by bacteria sooner or later. How safe it is depends on which bacteria find their way onto the food, how fast they grow, etc. It’s kind of a roulette wheel. The longer it sits out, the more dangerous it is.

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**Author:** ![rjk](https://avatars.discourse-cdn.com/v4/letter/r/ed655f/32.png) [@rjk](https://boards.straightdope.com/u/rjk)\
**Post date:** [November 2, 2000, 1:42am UTC](https://boards.straightdope.com/t/how-long-does-cooked-food-stay-good-at-room-temperature/39260/10 "2000-11-02T01:42:35Z")

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A note on botulism:

The bacteria may not grow in acidic conditions, as Smeghead says, but acid will not destroy the toxin. I read a few days ago about a case of botulism fron home-made pickled eggs. The article is at [http://www.ama-assn.org/ama/pub/article/1948-3071.html](http://www.ama-assn.org/ama/pub/article/1948-3071.html).

(Just doing my part to keep food paranoia alive!)
