My family and I were going through my grandmother’s apartment after her passing to get her estate in order. After all was said and done, I got a bunch of alcohol she had for guests mostly, including two types of whiskey (scotch and regular), some gin, and three flavors of vodka. I tried some of the Crown Royal and it didn’t taste too good. Also didn’t taste like the last glass of whiskey I had before. Of course I always hear about stuff aged 4 years or 12 years etc. so I wonder if it’s a “gone bad” thing or a me thing.
Aging for whiskey and scotch is done in specialized wood barrels with specific environmental conditions, not in the bottle.
If the hard booze bottles been opened for a long time, it’s always possible some evaporation, or other slight changes have occurred that may impact taste, but still perfectly safe. Assuming it’s 80 proof and up.
Throw out open wines if you’re not comfortable determining if they’re still consumable and not spoiled.
TLDR: Toss opened bottles of wine, but any hard liquor should be safe, even if it taste is degraded.