Salt has been a part of man’s life for millennia. This is because over half our body consists of fluids which contain appreciable amounts of salt. Each day the body loses a quantity of salt which must be replaced in order to maintain the balance. The human body cannot manufacture salt and therefore salt forms an essential daily part of a healthy balanced diet. What a bonus, then, that it also improves the taste of most food!
For centuries, salt was difficult to obtain and therefore highly prized and as with any other highly prized substance, salt attracted the attention of the governments of the day as a source of revenue. Salt taxes were levied in countries such as France, England, China and India. In fact, the British salt tax in India led to one of Mohandas Mahatma Gandhi’s most famous campaigns of civil disobedience.
Today, there is a bewildering array of salt available at both supermarkets and speciality stores. The finished product may be fine crystals, larger crystals, or flakes; and the processes to obtain it varies according to whether it is rock salt or sea salt. Some salts are suitable for cooking, but others are classified as “finishing salts” which should only be used on prepared food lest the subtleties of their texture and flavour be lost. Confused? Let’s take an armchair journey to discover some of the better-known and the more unusual salts from around the world.
Table salt or iodized salt (refined)
This is the most readily available and cheapest form of salt, made all over the world. It is obtained either by mining or driving water into an underground salt deposit, formed by seawater millions of years ago. This process forms a brine which is then evaporated leaving dried salt crystals. The salt consists of about 99% sodium chloride and is then refined to make it very fine-grained and pure white. Anti-caking agents and iodine are added – the iodine is added to prevent goitre (swelling of the thyroid) which may be a problem in areas where the soil is deficient in iodine. This type of salt often has a bitter, acrid aftertaste and may smell “chemically”.
Kosher salt (refined, not iodized)
This has nothing to do with the salt actually conforming to the Kashrut Jewish dietary laws. However, kosher meat needs to have the blood drained from it and as kosher salt has larger crystals than table salt which remain on the surface rather than dissolving, it is ideal for coating the meat in order to draw out the moisture. Kosher salt is made as described above, but the brine is continually raked, resulting in larger crystals. It can be used for most of the same applications as ordinary table salt, but is not recommended in baking or recipes where there will not be enough moisture to dissolve the large granules. Chefs often prefer to use kosher salt as its larger crystals are easier to handle for even sprinkling on food.
Rock salt (refined/unrefined)
Rock salt is mined from large underground deposits called beds or domes, as opposed to being extracted by evaporation. It is crushed into manageable chunks and hauled to the surface, where it is screened, bagged, and shipped for further processing. Much rock salt ends up as non-edible large crystals used in applications like de-icing roads and to soften hard water (e.g. in dishwashers). But some particularly fine examples are broken into manageable-sized crystals to be used as table salt, including:
- Himalayan rock salt, said to come originally from Alexander the Great’s salt mine in Kashmir, Pakistan, is mined by hand and sold as large pinkish crystals about the size of golf balls. The crystals have to be freshly grated for use, resulting in very fine powdery salt which retains a pink tinge. This salt is said to contain an almost identical set of elements to those found inside the human body: 84 of the possible 92 trace minerals, in the same proportion as naturally exists in our blood.
- Bad Ischler Kristallsalz is an iodized rock salt from the town of Bad Ischl near Salzburg (literally “salt town”) in Austria. Bad Ischl is in the Salzkammergut which literally means “Estate of the Imperial Salt Chamber”, referring to the authority charged with running the Hapsburg empire’s salt mines. A non-iodized version is only available on request in Austria, where legislation requires iodization of table salt.
Sea salt (refined/unrefined – fine-grained varieties may be iodized)
Some table salt is derived from seawater which is heated in order to evaporate the water and leave the salt. Because this process is more expensive than salt produced from mines, you will usually pay a premium for sea salt. Sea salt can either be sold as a fine-grained product, as larger crystals, or as flakes.
The most famous English example is Maldon Sea Salt which is made along the east coast of England. Water is drawn from the ocean during twice-monthly spring tides (when the salinity is at its peak) and pumped into stainless steel tanks. From there it is pumped as needed into shallow stainless steel evaporating pans constructed over an intricate system of brick flues which contain heating ducts. The temperature is carefully regulated in order to encourage evaporation and the formation of salt crystals. These crystals eventually sink to the bottom of the evaporating pans and from there they are “drawn” – raked out by hand using traditional wooden rakes. The resulting salt consists of flaky, pyramid-shaped crystals and is ideal as a finishing salt.
Fleur de Sel – literally “flower of salt” (unrefined)
This premium salt is regarded as a finishing salt – once it has dissolved and mixed with other ingredients much of its characteristic crunchiness and subtle marine flavour will have been lost. Fleur de Sel from Brittany in France is the best known, but versions are also produced in the Camargue region of France, along the Algarve coast of Portugal (where it is called Flor de Sal) and St Helena Bay in South Africa.
Obtaining Fleur de Sel is a complicated and labour-intensive business. Seawater is guided from the ocean along a system of channels where natural evaporation increases the salt concentration in the water from 27g/l to 300g/l. This concentrated brine is flooded into shallow coastal pools where it is left to evaporate naturally. During the process of evaporation, salt crystals slowly form in a thin layer on the surface, particularly on windless days. The task of harvesting this delicate layer of salt is done entirely by hand using traditional wooden rakes called lousses à de fleur. The rakes are delicately wielded by specialists known as paludiers who know how to rake only the fine layer of salt off the surface of the pond, producing flaky, off-white and slightly moist salt. No mechanical machinery is ever used and no metal ever touches the salt; nothing is added and nothing is removed. Because conditions must be just right for Fleur de Sel to form (it can only be harvested from May to September, on windless days), the yield is only about one pound for every 80 pounds of Sel Gris (see below), making this an expensive but worthwhile commodity.
Sel Gris – literally “grey salt” (unrefined)
This salt is moist and unrefined and is closely related to, but more robust than, Fleur de Sel. It is produced in the same shallow coastal pools as Fleur de Sel (described above), but is raked up from the bottom of the pool rather than skimmed off the top. This salt is also not collected by machine but by hand using traditional methods – although the paludiers rake the bottom rather more vigorously than when harvesting Fleur de Sel! The salt flakes have a very definite green/purple/grey colour and distinct flavour, both obtained from its contact with the minerals in the pool’s clay bottom. Like Fleur de Sel, Sel Gris is only harvested between May and September, making it expensive but less so than Fleur de Sel.
Hawaiian Alaea Red Salt (unrefined).
This salt is produced from Hawaiian waters. A natural mineral called Alaea (a red clay from Kauai of volcanic origins, rich in iron oxide) is mixed in with the salt crystals during evaporation under the sun, which imparts the red colour. The salt is said to have a pleasant taste of toasted hazelnuts and it is exceptionally high in iron, because of the presence of iron oxide in the Alaea clay. It is used by Hawaiians in traditional ceremonies to cleanse, purify and bless tools and boats.
Hawaiian Black Lava Salt (refined).
This sea salt is evaporated in pools above ground that formed naturally from old lava flows. The colour is not natural but created by bonding high quality, activated charcoal to pure Pacific Ocean sea salt. Hawaiian Black Salt excels as a finishing salt and has a spectacular deep black colour. Its charcoal content is also said to give it detoxifying properties.
Indian Black Salt (unrefined)
Nirav Black Salt (also known as Sanchal or Kala Namak) is not a sea salt but a volcanic rock salt or saindhav and is mined in central India. This salt is not really black at all but rather a very deep burgundy-pink, as a result of the presence of trace minerals and iron. The salt has a distinctive sulphur taste and smell that somewhat dissipates upon cooking. It is also used in Ayurvedic medicine as a digestive aid.
Australian Murray River Pink Salt (unrefined)
Australia’s Murray-Darling Basin was once the bed of a shallow sea which eventually disappeared, leaving behind its salt in the soil. Low rainfall and high evaporation have combined to concentrate salt in the groundwater.
This pink salt is produced by evaporating briny water from Lake Mourquong, into which saline groundwater is pumped to alleviate the salinity problem. The brine contains sodium, potassium, calcium, magnesium and iron, resulting in a colour that varies from deep pink to light apricot.
The essential flavour of the infinite
Although salt is no longer the precious commodity it once was, it seems likely that we will continue our love affair with salt in all its various forms. Perhaps it is because of the flavour it imparts to food. Or perhaps it is because, as Pablo Neruda wrote: “… the least wave of the saltshaker teaches us … the essential flavour of the infinite.”
By Jeanne Horak-Druiff
Jeanne Horak-Druiff is based in London
and writes the food blog CookSister!.