The company SunSalt was established by Duncan and Jan Thomson in 1983 as a boutique offshoot from a commercial salt-production venture. The processing plant also produces magnesium sulphate (commonly known as Epsom salts) and cheaper industrial salts. SunSalt operates three evaporation pans: two in New South Wales and the other in north-west Victoria. We visited the Mourquong Basin, 13 kilometres from Mildura: a naturally occurring semi-circular salt basin, eight kilometres in diameter. The basin is a natural depression in elevated land, creating conditions perfect for salt production.
Brine is pumped from underground reservoirs 45 metres below the earth’s surface, and diverted into the Mourquong Basin. It rises above the ground from the Parilla Aquifer, an ancient inland sea. Pumping the water out is part of the government-sponsored Buronga Salt Interception Scheme, in place to divert salty water from entering the Murray River system at Mildura.
This brine yields twice the salt content of sea water and is reddish brown. It travels through several man-made locks along a supply channel and into a giant salt pan. At this point, the water is rich in both magnesium and calcium. The area resembles a moonscape, the odd, low-growing salt bush the only vegetation. On higher ground, orange groves are abundant on the horizon. The Riverina district, of which Mildura is a part, is also famous for its citrus production.
The water travels through several canals before making its way to crystalliser ponds that have been laser-levelled. The laser-levelling creates a completely flat surface so that the salt water can dry in flat sheets that can be surface-scraped without mixing soil in with the salt. Facilitated by the depth of the pond, which helps enable sodium chloride crystals to form, the brine is evaporated by the sun. The area around Mildura coincidentally has extremely high evaporation rates (about ½ metres of water per year), which creates optimum conditions for the brine to crystallise.
The salt crystallises over the summer months and is then harvested, tractors pushing the salt into mounds that are metres high. It is transported to a nearby processing plant where the salt is slowly and gently passed beneath huge heating devices that dry it, though it does retain slight moisture. The crystals are sorted by size and are ready for sale.
FLEUR DE SEL
Fleur de sel is the salt that has the most romance about it: it is light, fine and fluffy, and this is actually the result of weather conditions on the salt pans. The name, meaning ‘flower of the salt’, originates from the village of Guerande, Brittany, where the salt was first discovered. The temperature in this region is milder than other parts of France. Atlantic currents run clearer. On warm breezy days without rain, a single day’s evaporation of salt crust atop the salt pond is harvested by artisan paludier (craftsman salt harvesters) as the fleur de sel. It is the least salty, purest part of the saline. In Australia, this salt is harvested in much the same way when conditions are right, but they are rarely perfect for creating fleur de sel, which is why it is the most expensive type of harvested salt. It is usually the result of drifts of salt, driven by the wind, that accumulate on the edges of the salt pan.
PINK SALT
Pink salt was around in ancient Egyptian times, first harvested from a wadi (dry river bed) north-west of Cairo. Its colour was a result of the mineral-rich soils where the salt water originated.
The pink colour of Murray River salt comes from the rich mineral stores of the inland sea Parilla Aquifer. The salt is full of nutrients from the soil through which it is mined.
GOLDEN SALT
Like pink salt, the colour of golden salt is the result of residual minerals in the brine from which the salt is harvested. Potassium, iron, calcium and magnesium – substances not found in other salty waters used to make table salt – are present and unadulterated. The golden salt is unwashed, unrefined, and as a result it makes an excellent, highly flavoured garnish. The crystals of golden salt are harder than that of pink salt or fleur de sel due to the minerals present. The water that is used for harvesting salt is quite acidic, adding to the distinct colour of both pink and golden salts.
WET SALT
This salt is harvested while the concentrated, salty-sweet brine is still present in the crystals. When stockpiled, the salt dries and is leached, resulting in an intensified flavour in the salt crystals themselves. This occurs as a natural progression when the wet salt is exposed to the atmosphere. Because the wet salt is bulldozed into piles before it is completely dry (other salts are dried beforehand), it has a strong, salty flavour. At Bécasse I use wet salt for marinades as the moisture in the salt carries flavours further. The wet salt crystals are delicate and have similar flavours to fleur de sel and pink salt; fresh without being too strong.