Salt for human consumption is produced in different forms: salt evaporated as well as cold refined, rock salt, sea salt (refined and unrefined), dendritic (contains ferrocyanide salts), fluoridated salt, and salt fortified with iron. Refined salt usually contains about 99.5–99.9% NaCl and some additives such as whitening and anti-caking agents to keep the salt crystals from sticking together as they absorb moisture from the air.
Salt is extracted from oceans and saline lakes (e.g. Great Salt Lake, Dead Sea, Caspian Sea, Issak Kul in Kyrgyzstan, Lake Eyre in Australia and Chilwa in Malawi), through evaporation of water to leave salt crystals that can then be harvested mechanically. Any impurities that are present in the brine are drained off and discarded prior to harvesting.
Salts are crystallized through a series of heating and cooling steps and then harvested using centrifugation. The physical changes that result in crystallization are the result of ionic bonds rather than covalent bonds.
Sea salt consists of about 98% NaCl with remaining 2% is constituted by trace elements like iron, magnesium, sulfur and iodine.
Sea salt has boomed in popularity in restaurants and supermarket aisles. Many gourmet chefs say they prefer it over table salt for its coarse, crunchy texture and stronger flavor. Manufacturers are using it in potato chips and other snacks because it’s “all natural,” and less processed than table salt.
The air near sea water contains salt particles that control the radioactive properties of clean background atmosphere by scattering sunlight. Sea salt is also used in cosmetics and as bathing salt, but takes high concentration of iodine, an essential element for human health.
Because of industrialization, it is usually blamed that due to pollution load it may receive various industrial effluents which are rich sources of heavy metals with negative impact on health like cadmium, nickel, zinc, molybdenum and iron.
Sea salt: Production and usage
