Sea salt being harvested in Sumenep on Madura Island, Indonesia. The water is evaporated and the salt is crystallize. They’re sea salt ponds, cultivated to produce pure snow-white sodium chloride for industry and for the table. The colors in the ponds come from unusual microbes that thrive in the evaporating brine and produce pigments to cope with the intense sunlight.
A few months ago I finally encountered the colors of that briny life up close, in a jar of salt from the Murray River region in southeastern Australia. The remains of salt-loving bacteria and algae give the crystals a beautiful pink blush and a faint, pleasant aroma.
These days, salts come from all over the world, in many hues and crystal forms and textures. But this welcome blizzard is borne on a whirlwind of obfuscatory hype. A gritty rock salt from Utah styles itself “nature’s first sea salt,” blasted as it is from the geologic remains of an ancient ocean. Despite being a mineral and thus inorganic by definition, a sea salt from New Zealand has somehow been certified as organic. Evocatively named “Himalayan” salt is likely to come from mines around 900 feet above sea level, in the Salt Range of northern Pakistan, about 100 miles south of the Lower Himalayan range.
We now have “selmeliers” to expound on the flavors and textures of all these salts, the terroir of rock salts and the “meroir” of sea salts.
And the salt expert and purveyor Mark Bitterman has called into question the palates of the many chefs and cookbook writers who routinely recommend the use of kosher salt, which he views as an industrial, soulless product that tastes bad. In his recent book “Salted,” an entertainingly opinionated, frustratingly undocumented tour through the new world of salts, Mr. Bitterman offers vivid tasting notes. He describes the flavor of pink Murray River salt, for example, as “distinct sunshine sweetness; tingle of warm minerals.”
And the flavor of kosher salt? “Metal; hot extract of bleach-white paper towel; aerosol fumes.”
Is this just hyperbole from a seller of artisanal salt? Or is it true that pure salt can have other flavors beyond simple saltiness? And can less refined salts taste so much better that they might be worth a hundredfold multiple in price?
These aren’t new questions for cooks, but at last sensory scientists have taken an interest and run careful taste tests to answer them. It seems as if most salts taste pretty much the same, but no salt, even the most pure, is merely salty.
Culinary salts generally come either from the oceans or from solid underground deposits of ancient seas. Both sources contain many different minerals, but the predominant one is sodium chloride. Most standard table salt is produced by injecting water into mines to dissolve the minerals, heating the brine to evaporate the water, and then handling the minerals as they precipitate to separate sodium chloride from the others, which generally have a bitter taste. Table salt is more than 99 percent sodium chloride.
Sea salts are produced from ocean water, either by slow evaporation in shallow ponds to make what is known as solar salt, or by rapid boiling over high heat.
Both kinds of salt may be made on artisanal or industrial scales, and both can end up more or less refined (more or less pure sodium chloride) depending on countless details of the process. The least refined sea salts, with the largest proportions of other minerals and moisture, are gray and clumpy rather than white and free-flowing. Flakes of highly regarded fleur de sel, or flower of salt, are harvested from the surfaces of salt ponds.
If salt crystals develop while submerged in brine, they turn out compact and solid, like the cubic crystals of table salt. If they develop at the surface of the brine, they form flat flake-like masses or hollow pyramids.
