The answer was found by Scottish distilleries in 1761. Wood was expensive, and to cut fuel costs, they turned to chemist Joseph Black. He realized that to improve the process he needed to understand why ice creams take time to melt. Black discovered that while they liquefy, the temperature does not rise because all the heat goes into changing the shape of the water from a solid to a liquid. Only when everything has melted will the temperature rise. Thus Black obtained the minimum amount of wood necessary to evaporate a given volume of whiskey.
In short, pure physics and chemistry applied to the world of ice cream.
