Frozen dessert is a dessert made by freezing liquids, semi-solids, and sometimes solids. They may be based on flavored water, on fruit purées, on milk and cream, on custard, on mousse (semifreddo), and others. It is sometimes sold as ice-cream in South Asia and other countries.

Freezing food preserves it from the time it is prepared to the time it is eaten. Since early times, farmers, fishermen, and trappers have preserved grains and produce in unheated buildings during the winter season. Freezing food slows decomposition by turning residual moisture into ice, inhibiting the growth of most bacterial species. In the food commodity industry, there are two processes: mechanical and cryogenic. The freezing kinetics is important to preserve the food quality and texture. Quicker freezing generates smaller ice crystals and maintains cellular structure. Cryogenic freezing is the quickest freezing technology available due to the ultra low liquid nitrogen temperature −196 °C (−320 °F).