Liquefaction is solid to liquid, sublimation is solid to gas, and sublimation is gas to solid.

The so-called "smoking" ice cream surface understanding is that ice cream will smoke, as if it were foggy. But the ice cream is still the original ice cream, but it smokes under the action of special raw materials. It is more layered than ordinary ice cream in taste, and the ice cream made is crisp in appearance and soft inside.

The principle of smoking ice cream is actually to use food-grade liquid nitrogen for refrigeration. The temperature of liquid nitrogen is below zero 196 degrees, which is a colorless, nontoxic and tasteless liquid. Liquid nitrogen is very cold. When ice cream is soaked in liquid nitrogen, it will be eaten in the mouth, and when it comes into contact with the mouth, it will emit smoke. This is a physical phenomenon. When liquid nitrogen meets ordinary ice cream, it will be hard no matter how you soak it. This ice cream is not edible, let alone smoking.