Does peanut butter go bad? I know it most likely does, but I found a jar of peanut butter that had a "best if used by" date of 12-02-04. I chucked it but I couldn't help but to open the jar. It still had oil, wasn't dried out and still smelled like regular peanut butter. It didn't give any indication that it was going bad like discoloration or fuzzy growth. However, I didn't proceed with the taste test.

Did I just waste perfectly good peanut butter? It wasn't the 100% all natural kind either, (had partially hydrogenated oil in it) so I wasn't upset about chucking it.

The oil can go rancid. It will taste funny, but you will know right away.

The oil can go rancid. It will taste funny, but you will know right away.

:eek: yUck! Bad oil?

After throwing out my peanut butter, I opened another jar of JIF that looked new. There was no indication of a date anywhere. It looked like it was drying out. I shoulda stopped there because it tasted like plastic. I guess that's what I get for snooping around the kitchen in the break room. :bang:

That's interesting, the trans-fat oil (partially hydrogenated) isn't supposed to go bad for a while. It's "solid" at room temperature, which extends its shelf life significantly. Two years would probably do it, I guess.

Natural peanut butter goes bad much quicker. The lack of hydrogenation keeps it liquid at room temperature (why you have to stir it).