La congelación de objetos forma de conservación que se basa en la solidificación del agua contenida en éstos. Por ello uno de los factores a tener en cuenta en el proceso de congelación es el contenido de agua del producto.En función de la cantidad de agua se tiene el calor latente de congelación.El calor latente del agua es la cantidad de calor necesario para transformar 1 kg de líquido en hielo, sin cambio de temperatura, en este caso es de 80 kcal/kg.Otros factores son la temperatura de la ventana inicial y final del producto pues son determinantes en la cantidad de calor que se debe extraer del producto.La congelación se define como la aplicación intensa de frío capaz de detener los procesos bacteriológicos y enzimáticos que alteran los alimentos.

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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 their grains and produce in unheated buildings during the winter season. Freezing food slows down 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 (or flash freezing). 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). Preserving food in domestic kitchens during the 20th and 21st centuries is achieved using household freezers. Accepted advice to householders was to freeze food on the day of purchase. An initiative by a supermarket group in 2012 (backed by the UK's Waste & Resources Action Programme) promotes advising the freezing of food "as soon as possible up to the product's 'use by' date". The Food Standards Agency was reported as supporting the change, providing the food had been stored correctly up to that time.

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