Hard liquor stays good. They apparently just found
crates of whisky in Shackleton's basecamp that are still drinkable. It's a big coup for the distiller in question, apparently, because they can now compare their current production with the old stuff.
What I need to know is the shelf life on an unopened bottle of Baileys. I have a bottle of Penn Dutch Egg Nog (pre-liquored, sealed glass bottle) that's been in the fridge too long too ... how long until they are classed as biohazards? There's no expiration date on the bottles.