title_body: Reroasting coffee beans after a couple of years - is it worth it?
upvoted_answer: Honestly, I would discard them. The flavor is developed by roasting, but once it’s gone, it’s gone. We are talking about volatile aromatic compounds, that likely have degraded or evaporated (yes, it may even happen in mostly airtight containers).
  Re-roasting may create some more, but assuming that the original roast was “as intended”, you would likely create unwelcome notes, like bitterness or burnt flavors.
  There’s also a good chance that the oils have oxidized, i.e. gone rancid.
  There’s nothing wrong with giving it a try, but I wouldn’t expect results worth the effort.