Salt is a crystalline mineral that is composed primarily of sodium chloride (NaCl) the taste of which is one of the basic human tastes. It is absolutely essential for animal life, but can be harmful to animals and plants in excess. Apart from being one of the worlds oldest, most ubiquitous food seasonings, salting is an important method of food preservation.

For human consumption, salt is available in a number of different forms: unrefined (sea salt), refined salt (table salt), and iodized (crystalline)

Obtained from sea water or rock deposits, salt ‘solids’ may be white, pale pink or light gray (edible rock salts may be slightly off white in colour because of the mineral content)

Salt has been known as a food preservative, especially for meat, for thousands of years.

The Neolithic people of the Precucuteni Culture were boiling the salt-laden spring water through the process of briquetage to extract the salt as far back as 6,050 BC, while an ancient salt-works operation has been discovered at the Poiana Slatinei archaeological site in Romania.

The harvest of salt from the surface of Xiechi Lake near Yuncheng in Shanxi, China dates back to at least 6,000 BC, making it one of the oldest verifiable salt-works.

Salt was also included in the funeral offerings of the ancient Egyptians from around the third millennium BC, as were salted birds and fish, while the Phoenicians traded Egyptian salt fish and salt throughout their Mediterranean trade empire.

The Azalai (salt caravans) crossed the Sahara on routes maintained by the Tuareg tribes. As late as 1960 the caravans were still transporting some 15,000 tons of salt, but this has now declined to roughly a third of this figure.

Hallstatt gave its name to the Celtic archaeological culture that began mining for salt in the area in around 800 BC. Around 400 BC, the Hallstatt Celts began open-pan salt-making and grew incredibly rich trading salt and salted meat to Greece and  Rome in exchange for wine and other luxuries.

The word salary originates from Latin, salarium which referred to the money paid to the Roman Army’s soldiers for the purchase of salt while the word salad literally means “salted”, originating in the ancient Roman practice of salting leaf vegetables.

An excessive intake of salt will result in symptoms such as nausea, vomiting, diarrhoea and abdominal cramps while a deficiency will result in headache, nausea and vomiting, muscle cramps, drowsiness, fainting, fatigue and possibly coma.

During the past century or so canning and artificial refrigeration have increasingly been used for the preservation of food.