By Franz Scheurer
Historically, dietary salt (sodium chloride) has been obtained by numerous methods: solar evaporation of seawater, boiling down of water from brine springs, and mining of ‘rock’ salt. In history ‘Salt making’ could be regarded as an agricultural occupation, as ancient references frequently refer to the annual production as ‘harvest’. Salt making was seasonal, beginning with the start of the warmer weather and ending with the autumn rains.
Arguably the quest for salt led to the establishment of the ancient trade routes in the ancient world. The historian Herodotus described caravans heading for the salt oases of Libya and great caravan routes also stretched across the Sahara, as salt from the desert was an important commodity exchanged for West African gold and slaves. Similarly huge salt deposits were mined in northern India before the time of Alexander the Great and in the pre-Columbian Americas, the Maya and the Aztecs traded salt, which they used in food, in medicines and as an accessory to religious rituals. In China evidence of salt mining dates from as early as 2000 BC.
Homer termed salt ‘divine’ and Plato referred to it as ‘a substance dear to the gods’. Aristotle wrote that many regarded a brine or salt spring as a gift from the gods. In the bible it is written: “This is a perpetual covenant of salt before the Lord with you and your descendants also”. In the Orient, salt was regarded as a symbol of a bond between parties eating together. In Iran ‘unfaithful to salt’ referred to ungrateful or disloyal individuals. The English word ‘salary’ is derived from salarium, the Latin world for salt, which was the pay of Roman soldiers. Roman sausages were called ‘salsus’ because so much salt was used to make and preserve them.
The preservative properties of salt maintained its popularity throughout history. It helped preserve the food for marching armies and migration of peoples.
During the 18th century other industrial uses for salt were discovered. The invention in 1792 to make sodium carbonate began the carbonated water industry and by 1850 a staggering 15% of the salt in France was going into soda. Since that time non-dietary uses of salt have far outweighed its employment for culinary purposes.
Governments realised the importance of salt early on and imposed taxes on it. During the 19th century in the United States, a salt tax helped build the Erie Canal and during the twentieth century in India, Mahatma Gandhi revolted against a salt tax, leading to the famous ‘March to the Sea’. Such has been the importance of salt that one historian has written: ‘Clearly, anyone who can control the salt supply of a community has powers over life and death. The control of water being more ubiquitous than salt, is not so simple to put into effect.” (Bloch 1976)
Salt is an essential item in the diet of humans and animals. Its definite taste is easily detected and it enhances the flavours of the food it is added to. Sea salt is still being evaporated naturally in bays or enclosures (hence the name bay salt in older books). The bays may be dried out completely or the salt crystals raked out of a saturated solution. Sea salt is also being made by evaporating the water over heat, and was once produced in large quantities by this method in wide earthenware pans.
Rock salt is found in deposits originating from the drying of ancients seas. It can be mined as a crystalline mineral, but modern production methods rely on the pumping over of water then evaporating the resulting brine.
Flavour of salt depends on the impurities present. Ancient seas didn’t necessarily have the same composition of those of today and some deposits may contain poisonous substances, such as arsenic. Salt may be stained red with iron, yellow or grey with other minerals.
The selection of the right salt is most important in cooking. Flavours vary greatly and the size of the crystals matter, as well.
Below a description of some of the salts reasonably easily available in Australia:
‘Australian Sea Salt’ from the Great Australian Bight is washed clean, dried and remains unrefined. This is a bright white salt consisting of tiny crystals, with a clean salty flavour and a hint of kelp
‘Australian Natural Lake Salt’, harvested from the Koolyanobbing salt lakes in Western Australia comes in a course and fine crystal. Pure white, filtered and kiln dried it is sharp and minerally with a long-lasting taste.
‘Black Salt’ (Kala Namak, India) is a salt from India, which is brownish-black in lump form but pinkish-brown when powdered in a mortar. It is a reasonably mild salt with a slightly smoky flavour.
‘Fleur du Sel de Camargue’ (France) harvested from dried saltpans in the Camargue region of France this is a slightly off-white, fine crystal salt with grassy notes. It has an almost sweet finish.
‘Halen Môn’, (Wales, UK) is a pure sea salt smoked over Welsh oak, harvested in Wales. It exhibits fairly coarse, slightly yellow crystals and, as expected, has a pronounced smoky flavour.
‘Le Saunier Sel de l’Atlantique’ (France) is a creamy coloured coarse-grained salt from the Atlantic. It is gathered from the salt marshes, dried and crushed. It is unwashed and unrefined and retains an attractive earthiness and is very rich in magnesium.
‘Maldon Sea Salt’ (Essex. England) with its wonderfully flaky crystals is probably the most popular sea salt in the world. Tangy with overtones of iodine and complete free of any bitterness; it is a marvellous, multipurpose salt.
‘Marnoto Flor de Sal’ is an Atlantic salt, in fine crystal form, from Portugal high in potassium, calcium and magnesium. It is off white in colour and tastes herbaceous.
‘Murray River Gourmet Salt’ (Sun Salt, Mildura) is produced naturally from the underground brines in the Murray Darling Basin. The salts produced contain the naturally occurring minerals, as well as other elements from the brine, resulting in different tastes. These underground saline waters have been laying dormant for thousands of years and by utilising these waters, the environment is improved and a unique salt has been produced. It’s called ‘Salt Flakes’ and it is a finely flaked, wonderfully pink salt with a powerhouse of layered tastes. They also produce a variety of other salts, from yellow to grey in varying sizes of crystals and lumps.
‘Sel Gris’ (France) is a grey, coarse salt, ideally suited for flavouring stocks and pasta water. Strong, very maritime, with hints of iodine, kelp and wet grass.
References: The Cambridge World History of Food, The Oxford Companion to Food, The Cook’s Encyclopaedia, Duncan Thomson (Sun Salt) and my pantry.