Food preservation

Food preservation is about the ways and means which help to preserve food. Food spoils from bacteria if it is not treated. For thousands of years, humans have used methods of preserving food, so that they can store food to eat later. The simplest methods of preserving food, such as drying strips of fish or meat in the hot sun have been used for thousands of years, and they are still used today by indigenous peoples. The other ancient method is to use salt, and often drying and salting are done together.

Food is spoiled because microorganisms change it. There are five basic techniques which make food last longer:

1. Killing the microorganisms, or preventing them from multiplying
2. Contact of microoganisms with food is prevented
3. Certain additives prevent or slow the growth of microoganisms; this is often called curing

Usually several of the techniques are combined.