For more than ten thousand years, preservation methods have been perfected: salting, curing, smoking, pickling, refrigeration and the application of heat by cooking food.
The great development of the canning industry, the possibility of pasteurizing, lyophilizing or deep-freezing has meant a notable advance in terms of conservation. Among the most frequent conservation methods are the following:
- Dehydration: Involves the removal of water from a product by artificially heating the air. Desiccation is a simpler process, since it involves the extraction of moisture from the food in natural environmental conditions.
- Lyophilization: It is a drying process in which the passage from solid to gas occurs without passing through liquid. It is based on certain vacuum conditions: frozen water and water vapor are entrained and removed.
- Freezing: Freezing is understood as storage in which the food is kept at a temperature of -18 degrees or lower, thereby prolonging its duration.
- Pickled: Salt and vinegar intervene together, simultaneously achieving preservation and providing a characteristic flavor. The preservative action of vinegar is due to the acetic acid it contains and the salt acts by dehydrating the food.
- Cured: Consists of the application of certain salts, generally nitrates, which have a protective action against bacteria.
- Salting: It is a conservation process based on the addition of salt in a more or less abundant quantity. It captures the water in the food, dehydrating it and depriving microorganisms of this vital element.
