Food preservation is the name for a number of processes that help to preserve food. This means that the food treated that way will go bad (spoil from bacteria) later that if it had not been treated that way. 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 in the 2000s by indigenous peoples.
Methods of preserving food [change]
Common ways of preserving food are:
- Heating the food or baking it (a hard corn-flour biscuit stays edible much longer than a bowl of fresh corn)
- Converting the food into a longer-lasting form (for example, fresh goat's milk can be converted into cheese or yogurt, which lasts much longer than fresh milk)
- Putting the food such as vegetables, meat, or fish in salty water (brine) (or covering it with dry salt)
- Putting the food in a jar with alcohol (ethanol) or vinegar
- Putting large amounts of sugar in the food (for example, as with jam or fruit jarred in sugar and water)
- Drying in the sun or in an oven
- Smoking the food with the smoke from burning wood
- Keeping the food cold or frozen
- adding sulfur dioxide (known as oxidation)
Multiple methods [change]
Many common methods use several of these approaches at the same time. For example, pickles preserved in a jar are heated then put in a mixture of vinegar and brine. Fruit jams and jellies are heated and mixed with a large amount of sugar. Some preserved fruit is heated and then mixed with alcohol (for example, Brandy) and a large amount of sugar. Smoked hams are cured in brine and then exposed to the smoke from burning wood chips.