In very cold climates, the easiest way to keep Coca-Cola from freezing is to store it inside, in a heated shop or home.
Exposed to the elements for an extended time, Coke would freeze, causing an indefinite postponement of the pause that
refreshes. Actually, before the soda could freeze, the can itself would burst.
The aluminum cans are structurally incapable of handling the change in pressure brought on when the liquid within them freezes. So, even though Coke is best when served cold (Coke officials say 40.1 degrees Fahrenheit or below is ideal), it won’t keep well in a snowbank.
It can, however, be stored in an outdoor vending machine, even in subfreezing temperatures.
The trick to outdoor vending machines is to keep them warm enough to prevent the beverage from freezing, but cool enough
that the Coke isn’t heated.
Warm Coke is even less appealing than frozen Coke. Large heating units, therefore, are not desirable. Instead, cold-climate Coke machines are equipped with a sixty-watt light bulb and a fan. The light bulb, situated at the top of the machine, generates heat; the fan, situated at the bottom of the machine, circulates cold air from the bottom of the machine to the warm area at the top.
Cans of Coke are stacked lengthwise in a chute inside the machine. The circulation of air within the machine ensures that all the cans are exposed to warm air; because hot air naturally rises, and because the source of heat, the light bulb, is at the top of the machine, the cans at the top of the chute stay warmest.
When a person deposits money in the machine, the bottom-most can in the chute is dispensed and all the other cans drop down one position.
With each drop in position, the cans experience a corresponding drop in temperature, so that by the time a can reaches the bottom of the chute and is dispensed, it has achieved perfect drinking temperature.