The thing you get when you leave a beer in the freezer too long. Because beer has alcohol and is under pressure it's freezing point is lowered from 32 to 22 degrees. So it can me left in the freezer ten to twenty minutes with no problem. Creating a super cold beer.
But if you leave it too long and then try to drink it quickly then stop suddenly the release of CO2 gas drops the beer below it's freezing point and turns the rest of the beer in the can to slush.