The quality and taste of alcohol tends to deteriorate with temperature swings, particularly towards the hotter side, exposure to light and high humidity. This is why the general advice is that a garage is not the best place to store alcohol.
Storing beer warm for extended periods of time will shorten the beers shelf-life. The same flavor loss results from beer being stored in your car's trunk for three days at 90°F as beer being stored at room temp (72°F) for 30 days and beer being stored at 38°F for 300 days.
Myth #8: Properly Stored Beer Doesn't Go Bad It's food, after all, so it will eventually spoil. Most beers will last about six to eight months when kept in a cool, dark environment, though micro brews and home brews often have a shorter shelf life when it comes to optimal flavor.