My housemates have gathered up a bunch of old food sitting around the house that they don’t want anymore, and one thing they found was a big jar of peanut butter. I’m a big peanut butter fan so I’ll gladly take it, but it says the “expiration date” was for back in July. I’m not sure how peanut butter can go bad, especially since I don’t think it’s even been opened. I imagine it’s still good, but how long will it be good for past the posted date? It is quite a lot of peanut butter…
I think that if it’s bad eating it with some crisp apples and cold milk will probably dilute it enough that you’ll be ok.
(sarcasm, I have no clue)
Go bad???
shudder That stuff is the work of Sa… um, I just don’t like it.
Seriously, it probably does, but not for a long time. You should be fine with “back in July”, but “July 1999” might be a different story.
Just one other point which may be relevant to this…
For decades, Australian food had expiration dates on the label (or actually, “expiry dates” as we called them here), but a few years ago, this was changed to a “Best Before” date, with the government strongly hinting that the dates were vastly too conservative. For a plastic-wrapped tray of steak from the supermarket, I might take the date pretty seriously. Milk too. But even for those, a day or so outside is probably fine. But for an oily, salty, and vacuum sealed foodstuff like peanut butter, heck I’d be game (if I liked the stuff) at twelve months or more.
Slightly hijacking this, but my dad tells a story of a bored, pimply teenage checkout clerk being asked the expiry date of some food or other by an aggressive, angry old woman. He tells her the date.
What happens then?", she demanded.
Adopting a Vincent Price voice and manner, he said, “IT EXPLODES!!!”
Heh.
Peanut butter has a very very low water activity, which means very few microorganisms can grow in it. You might see some mold or other fungus someday, but usually it’s good for a very long time, at least from a microbial standpoint.
Now, the fats can oxidize and go rancid, but basically, if you don’t see any fuzz, and if it doesn’t taste funny, it’s fine. Bon appetit!
That’s not a trivial issue. Rancid peanut butter (like any rancid fat,) will taste like ASS. But if it is still sealed, then it will have had very littlecontact with oxygen, and therefore probably not be rancid.
And peanut butter takes a hell of a long time to go rancid, even after being opened- that’s why you don’t have to keep it in the fridge.
I think you’ll probably be fine eating it.
Yeah. Just don’t drop any chocolate in the stuff and you’ll be fine.
Depending on the age, the oil may have separated out a little, but all you have to do is stir it back in.
Peanut butter is one of God’s favorite foods.
As long as it hasn’t been opened there is no way you will find life inside. A whole industry depends on it.
So you’re saying that it would be more accurate to label it with an expiation date?
I have had PB go rancid, but it was a previously opened jar that had a lot of surface area exposed to air and sat for quite a few months. If it hasn’t been opened, it’s probably fine, and even if the top layer has gone yucky, you should be able to remove that part and the rest will be OK.
If it has gone rancid, and you happen to eat some, be prepared for everything you eat the next week to taste like rancid peanut butter. This is the voice of experience talking.
Is peanut butter with the jam already in it in stripes (I think I vaguely remember a brand named Koogle, from my childhood) likely to go bad sooner because of the sugars/fruit?
Peanut butter will keep for a long time, but based on the age of the jar, I have to ask: is it Peter Pan or Great Value brand, and if so, what’s the code on the lid? You might remember that about a year or so ago, there was a recall because of salmonella contamination. Details from the FDA can be found here.
I once had an unsealed (screw-top only, no foil), unrefridgerated jar of peanut butter keep just fine for two years. Made a hell of a sammich.
What they said. Yeah, it can go rancid, which means it’ll taste strange–over months or years. I don’t know what that means to its nutritional value. If it’s been sealed, & not under extreme heat, it should still be fine within six months of its expiry, & if it’s not, you could tell by looking, tasting, & maybe smelling, that the fats have gone bad.
In that vein, I’ve eaten sesame butter that was years past its expiry. It was ugly tasting, hard to swallow, but not a huge health problem.
Then again, I once ate a slice of pizza that had been sitting out at room temperature for a week or more. ymmv.
Elendil’s Heir, if I remember correctly from Biology 120, jam takes an act of Congress and the agreement of at least seven minor deities to spoil.
Well put. All that sugar is very hydrophilic, which means there’s not much water floating (you should pardon the expression) around loose for microbes to put to use. That’s the reason we have jams and jellies in the first place – people wanted a way to have fruity goodness around even when the fruits themselves were long out of season. Molds can be a problem, but if it ain’t furry, the jam’s probably OK.
Right. It isn’t that outdated and it hasn’t been opened thus it is likely OK. But open it and smell it, you can tell if it has gone rancid.