We're going on a long flight with our family tonight. I prepared peanut butter sandwiches for the kids, and would like to pack it already to avoid the last minute rush (or forgetting them). We're not leaving for another 12 hours or so, and it will probably be eaten a few hours after that. (I'm not so concerned about mushy sandwiches because these are little kids, they won't mind.) Bread and peanut butter individually can be stored at room temperature for a significant amount of time... Can I leave my peanut butter sandwiches out for ~15-20 hours?

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    I've never seen a notice on store-bought peanut butter to store it in a refrigerator after opening, so assuming your PB doesn't have this notice, it should be perfectly safe. If including jelly, should also be fine as Joe describes below. – Dolan Antenucci Mar 25 '15 at 2:20

I've done it before without problems. Even if they're peanut butter & jelly (something that's typically stored in the fridge), it has so much sugar in it that it's inhospitable to microbes.

If you want to play it extra safe, and the sandiwiches won't be easten shortly after you leave, you could place them in the freezer and then let them thaw in your bag.

... all that being said, if you're in the US, the TSA considers peanut butter to be a gel, so won't let you fly with a container of it. I have no idea what their rules are in sandwich form. (I've never tried it, as I typically fly w/ cold cut sandwiches, and just take them straight from the fridge before I go).

update from Erica : "I have flown with peanut butter sandwiches in our carryons. New TSA rules mean pulling it out of bags to send through the scanners, but they had no objections."

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    I wouldn't freeze them, I think that would definately make the bread yucky soggy. I would recommend eating them before getting to the airport, like has already been said, TSA might not let you through. – Escoce Mar 19 '15 at 13:59
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    @Escoce : it depends on the type of bread. My mom would make sandiwches for a week & freeze them so that you could just pull one out in the morning. Firmer sandwich breads like pepperidge farm hold up just fine. I don't know how well it'd work with today's overly soft breads, or artisinal rustic loaves. I should also mention that for years my mom would buy loaves of sandwich bread & freeze them; the bread ends up a bit firmer than if you didn't freeze it, but it was what I grew up on for sandwiches. – Joe Mar 19 '15 at 14:46
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    @Escoce : If it thaws while tightly wrapped, it's not an issue. You could wrap it in a paper towel first to help mitigate any problems, but I don't remember it being an issue growing up (admittedly, it's been a few decades) – Joe Mar 19 '15 at 14:54
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    FWIW, I grew up eating pb/j sandwiches for lunch, which were assembled using frozen bread slices (store-bought white bread) in the morning (thus pb/j not frozen), and by lunch the sandwiches were defrosted. The bread was a bit moister, but not soggy. Your mileage may vary. :) – Dolan Antenucci Mar 25 '15 at 2:16
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    I have flown with peanut butter sandwiches in our carryons. New TSA rules mean pulling it out of bags to send through the scanners, but they had no objections. – Erica Aug 1 '18 at 10:11

They can be considered bad when the bread becomes moldy. If it is regular bread with normal preservatives then I would give them about 7 to 10 days before not eating them. Peanuts last stupidly long and with all the sugar they put in peanut butter the microbes almost cannot grow in it. I would be more concerned about the staleness of the bread before woring about anything being unsafe.


yes, why not? I've eat 1 -2 days old sandwiches of peanut butter and a lot of other things (ham, chiken, chocolate, cheese...) without problems ;) 15-20 hours is not too much. I think, only raw eeg could be unsafe.

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    Just because you are fine doesn't mean it was a safe. Time and Temperature guidelines are set to ensure every ones safety in all most circumstances, this includes younger children, and immuno compromised people. – draksia Mar 19 '15 at 12:23
  • Well look at his name, he is from the dark side after all. Seriously though, very bad advice. It's certainly going to be fine for peanut butter on bread, but not as a general rule. – Escoce Mar 19 '15 at 13:58

protected by Community Aug 1 '18 at 7:08

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