Does liquor have a shelf life?
Distilled spirits do not mature once they are in the bottle so unopened bottles will not go bad unless they are stored improperly. Opened bottles on the other hand are exposed to some air over years and may lose some of their finer qualities, which may or may not be noticeable. However, cream liqueurs like Bailey's and Advocaat have a shelf life of around 18 months, after which you want to be careful before consuming. You may even see the sugars of some liqueurs crystallize over months or years, this is a good sign that you don't want to drink that anymore.
Will liquor freeze?
Simply put, yes, but the freezing point of any alcoholic beverage is lower than that of water. I guess the question should be "Will a bottle of vodka freeze in my home freezer?" The answer to that is "likely not." Beer, malt beverages and low proof liqueurs may get slushy, frozen or even burst if left in the average freezer for too long, but the more alcohol a beverage contains, the lower the freezing point. Typically vodka, gin, rum, etc. are 80 proof and need to reach around -34.44°C (-30°F) to actually freeze so you'll be safe if you want to quickly chill a bottle in the freezer. And, if you forget it there you can be pretty sure it will still be a liquid when you return.
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