Salt of the Earth

Salt, and our burning physical need for it, have built roads, launched wars, and raised revolutions.

The story of salt is a story of struggle. Though common in the earth's crust and ubiquitous in its seas, salt isn't always easy to reach. Thus salt-bearing donkeys have worn "salt roads" as they distributed the precious mineral across Europe, and salt-laden ships have beaten watery paths around the world. Roman soldiers waged war in exchange for the elusive stuff, and Venice flowered on salt-trading profits.

Even today, in remote regions of the world, the gathering of salt can be an all-consuming task. In search of salt, the Kurelu women of Irian Jaya in the Indonesian archipelago undertake a two-hour trek up to a mountain spring that delivers naturally salty water. They soak strips of banana-tree stalks in the spring, then carry the water-logged sticks back home, according to author Peter Matthiessen's account in Under the Mountain Wall. When the fibers are dry, the women burn them on a rock and collect every speck of the resulting ash. Then, on festive occasions, the Kurelu sprinkle the salty crumbs on their food.

Salt, and our burning physical need for it, have built roads, launched wars, and raised revolutions. Its Latin name, sal, is the root of the words salary, salad, sauce, and sausage.

Even when salt became plentiful, humanity's nonnegotiable need for it encouraged many governments to tax it onerously. French officials were particularly enthusiastic about the salt tax, which by 1710 had reached 140 times the cost of salt's production. In modern terms, that would put the cost of a canister of Morton's at $65.

So between geology and greed, most of our time on the earth, until relatively recently, has been troubled by a nagging question: Where will we find our salt today? But now machines easily and cheaply extract this coveted mineral from huge underground deposits. Now, we have the luxury of asking a new question: Which salt shall we sprinkle today? And the increasingly popular reply is sea salt.

Sea salt, unlike common table salt, naturally contains a variety of minerals found in seawater. If the difference in flavor epitomizes subtlety, the philosophical difference is unmistakable: Unlike highly processed table salt, sea salt is a whole, natural food.

Sea-salt harvesting is an incalculably old profession. If there's no rush, harvesting can be as simple as trapping seawater in a pond and letting the sun and wind concentrate the brine until salt crystals form and drop to the bottom. If time is of the essence, you can collect seawater in pots and use fire to boil the water off. But the more attention you pay to the process, the better your salt will be. That's because not all of the ocean's minerals are savory.

Seawater is, by content, a little under 3 percent salt. But it's also nearly 1 percent other minerals. And as seawater becomes concentrated, one of these, calcium sulfate, crystallizes to form gypsum. If you've ever nibbled Sheetrock, you've probably concluded that no matter how natural gypsum is, it wouldn't do much for cucumber slices. So the professionals encourage gypsum and salt to settle separately by carefully managing the flow of water into ponds.

When salt first starts to crystallize, a chemical marvel occurs. If the sun and wind cooperate, delicate crystals form at the surface of the pond. Left to their own devices, they'd grow fat, and sink. But if instead they are skimmed to poolside--and if the pool is French--these fragrant and complex crystals are known as fleur de sel. A recent shortage of "flower of salt" has pushed prices as high as $33 a pound. (See "Crystal Persuasions," right.)

Along with minerals, organic crystals of sea salt may incorporate microorganisms. As with cheese, these microbes can impart nuances to the finished salt. Salt-loving bacteria, for instance, often tint crystallizing sea salt a surreal shade of pink. (Alas, this fades if the salt is dried in sunlight.) Single-celled algae may impart a floral scent for which fleur de sel is known. Finally, particles of clay and even sand from the pond may color the salt.

To treat a sore throat, I once dissolved sea salt in hot water. The sediment in the bottom of the glass was generous in quantity and diverse in form. Likewise, one jar of fleur de sel contained bits of plant fiber and a well-preserved ant. While I find such tokens of organic authenticity endearing, they did move me to scrutinize the pinch bowl whenever company was due for dinner.

After salt artisans harvest their crystals, they rinse them with saltwater to flush away debris that may have found its way into the pond. That's it. When you eat sea salt, you may eat clay, traces of minerals from aluminum to zinc, and the carcasses of deceased microorganisms. Mind you, those trace minerals won't keep you alive--you'd have to eat about 19 teaspoons of sea salt to get your daily dose of magnesium, for instance--but they're in there.

Even that table salt in the shaker is, or was, technically, sea salt. Long before dinosaurs roamed the American West, vast seas were making incursions into the belly of North America. Rivers that flowed into these temporary oceans delivered minerals they had leached from the surrounding rocks. The rivers were especially generous with halite--rock salt, or common salt occurring in solid form as a mineral. The seas are long gone, but the salt remains. As the oceans dried up, the salt and other minerals sank to the ocean floor. These salt deposits were gradually buried under other rocks. It's this antique sea salt that seasons most modern foods.

But you'd hardly recognize it if you descended into the mine. The old salt, for starters, isn't white, and it doesn't come in neat little crystals. If anything, it resembles quartz. It's cloudy and lumpy and veined with gray, red, and other colors from gypsum and shale. It needs, to the thinking of most folks, processing.

Modern salt miners drill into the deposits and pump in water. When that water has become suffused with salt, they retrieve it and treat the brine with chemicals to remove the minerals that once occupied the ocean. They heat the brine to evaporate the water. To the dry crystals, they add potassium iodide to ensure that our thyroid glands thrive. To prevent the flighty iodide from evaporating, they add a pinch of dextrose (a natural sugar). They add a touch of sodium aluminosilicate to keep the salt, which attracts moisture, from caking in humid weather. And voilà: Salt has become a uniform, colorless chemical that pours even when it rains, to paraphrase Morton. That's the general idea, anyway. About 20 different chemicals--some natural, some not--are approved as additives in table salt, and manufacturers mix and match for desired results.

Now, whether "fresh" sea salt tastes better than this processed version is a matter of opinion. Beauty, you might say, is in the palate of the perceiver.

If yours is a perceptive palate, the happy news is that sea salts are now becoming available in a dazzling variety as cooks cotton to them (see "Crystal Persuasions," page 84). And there's more good news on the health front.

For one thing, salt isn't the devil's own dandruff, contrary to the warnings of national health agencies. For decades, salt's sodium content has been demonized for raising blood pressure. But a large body of research now argues that only a minority of the population is sensitive to salt. The journal Science published a review of all the research in 1998, in which the author concluded that even cutting the nation's salt intake in half would produce such a tiny reduction in blood pressure as to be "meaningless" to the general public.

The next happy revelation is that people with diets rich in whole, natural foods have little need to worry about consuming too much salt. That's because most of the approximately 1 to 3 teaspoons the average American consumes every day is hidden in processed foods--canned soup, bottled spaghetti sauce, flavored rice, and the like. If you steam your own rice, stew your own stew, and simmer your own tomato sauce, you avoid boatloads of salt.

In fact, whole foods are often so low in the stuff that if it weren't for the saltshaker, you'd spend your entire day chewing just to capture the salt you need. In a single day, you'd have to eat about 2 1/2 pounds of chicken, close to 3 pounds of beef, and more than 100 small potatoes to nudge the government's recommended limit of 2,400 milligrams of sodium (about a teaspoon).

Granted, even that is nearly five times the amount you really need. But you do need salt. It regulates everything from blood chemistry to cellular and nerve functions. People who don't get enough of it suffer muscle cramps, fatigue, and dehydration. They are also liable to revolt, as Gandhi demonstrated with his 1930 Salt March to the salt-crusted shore of the Arabian Sea. When the people of India realized that the British Crown was taxing something as natural and plentiful as salt, their thirst for independence sharpened.

The history of our relationship with salt follows a trajectory common in the story of many of our basic needs, such as clean water or mold-free food. First, we suffer shortage and hardship. Then, through native wit, we discover a way to purify, preserve, and produce the coveted commodity in huge quantities. But after enjoying the cheap and plentiful item for a while, we begin to realize that we have lost something in the bargain. And with one foot safely in the modern world, we reach back to recover that spice of life, variety. Uniform, white crystals of salt have their place, perhaps. But in the center of the table sits sea salt: a pinch of the ocean and a dash of the marsh, gathered by the sun.

For more about salt, see Resources, page 126, or visit
Crystal Persuasions

(Also known as alaea or Hawaiian sea salt)

This mixture of salt and powdered Hawaiian red clay is rich in iron. The clay adds eye appeal and iron and takes a little edge off the salt, too.

Uses: Alae makes a colorful and flavorful garnish for pale foods. It seems especially good for earthy foods--potatoes, beets, cottage cheese. One producer swears by his salt as an overnight meat rub.

Price: $6 to $48 per pound

(Also known as Redmond RealSalt)

Table salt with a twist. Like table salt, this product is mined from ancient sea-salt deposits. It's not chemically purified--just pulverized--and may contain confetti-like red and black mineral specks. But it is carefully mined to avoid including the undesirable minerals you would commonly find in the inedible rock salt used to de-ice roads and sidewalks.

Uses: Cook with it or sprinkle it on finished foods. Rock salt may require grinding for table use and isn't suited for baking.

Price: $2 to $7 per pound

The "flower of salt" is raked from the top of shallow ponds of evaporating seawater on an island off France's Atlantic coast. The crystals are small, porous, and faintly sweet. The airy crystals are easy to crumble between the fingers, assuring good distribution over food.

Uses: At its price, it's definitely for finishing a dish. Recipes often recommend it for simple vegetables and seafood.

Price: $17 to $33 per pound

Mined and processed in the same way as table salt, kosher salt is simply produced in a different shape through a compactor that creates large flakes mechanically. Potassium iodide is not added.

Uses: Cooks who take a hands-on approach find kosher salt's big flakes more pinchable than table salt's crystals.

Price: $.70 to $1 per pound

(Also known as sel de mer; sel gris, or gray sea salt; sel marin, or bay salt)

This naturally evaporated sea salt is produced all over the world. Moist and gray, it comes in coarse or fine crystals. Sometimes minerals are added, as with lava salt. It may even be treated with smoke.

Uses: Same as edible rock salt

Price: $3 to $14 per pound

(Also known as common salt)

This ancient sea salt has been mined, chemically demineralized, and recrystallized as small, uniform grains. Primarily composed of sodium chloride, it contains additives.

Uses: The fine grain size assures even distribution in baking. It often contains iodine, which we need in our diet.

Price: $.20 to $.25 per pound
Salt through the Ages
Time immemorial

Hunting peoples got the salt they needed from meat. As farmed grains replaced meat in the diet, the need to add salt arose.
1000 B.C.

Salt miners sink shafts close to 150 feet into the salt mine in what is now the Austrian valley of Salzkammergut.
252 B.C.

The first brine wells are dug in China. Brine is pumped through bamboo tubes to a boiling house, where salt is extracted through evaporation.

The Erie Canal opens, greatly easing distribution of heavy, bulky salt. Financed by the state of New York with its salt tax, the canal is nicknamed "the ditch that salt built."
2700 B.C.

A Chinese treatise on pharmacology refers to some 40 varieties of salt and describes production methods that would be familiar to a modern salt producer.
506 B.C.

Rome, stung by the rising prices charged by salt traders in the Roman port of Ostia, takes control of the sea-salt works there.

The French Revolution is spiced heavily with rage against a crushing salt tax.

Richmond & Company, agents for Onondaga Salt, is founded in Chicago. Six decades later, the business would be renamed Morton Salt Company.

On December 20, the Union army deals the Confederacy a severe blow when soldiers demolish the saltworks at Saltville, Virginia. Salt preserved the meat that fed armies, and it was needed by horses, as well.

The Morton Umbrella Girl makes her debut with the slogan "When It Rains, It Pours," a reference to the addition of magnesium carbonate to the salt to keep it from clumping in humid weather.

Mahatma Gandhi leads the Salt March in India. This protest over salt taxation contributes to the eventual ouster of the British colonizers.

A maintenance engineer for the New Hampshire Highway Department is the first to sprinkle salt on the roads to prevent ice from forming.

Reflecting its booming business in industrial chemicals derived from salt, Morton Salt changes its name to Morton International, Inc.

To keep pace with consumer health and diet trends, Morton introduces Salt Substitute.
Seasoning Our Speech

• Roman soldiers were once paid with salt (salarium, the root of today's salary). Over time, the word salary came to include regular payments made with cash or coins instead of goods or services.

• When Pliny the Elder wrote the recipe for a poison antidote in the first century A.D., he added, at the end, that the concoction should be taken with a grain of salt. Years later, as the story goes, the formula's endnote was interpreted to imply skepticism about the antidote's effectiveness. Lexicographers aren't convinced about this origin of the phrase, however, so take this tale with a grain of you-know-what.

• To keep meat from spoiling, preserve it with salt, or salt it away. That's what you do with your money, too, when you're trying to preserve it.

• If you get a lousy seat assignment for dinner, you're sitting below the salt. The banquets of medieval European lords featured an elaborate saltcellar that dominated the head of the table, along with the VIPs.

• In Matthew 5:13, Jesus praises his followers as the salt of the earth. He also calls them "the light of the world," but that phrase lacked staying power.
Farming the Watery Fields of France

On those summer days when the sun shines and wind buffets the sea grass on the north coast of France, Stéphane Bouleau goes gathering salt. Bouleau will carefully rake a few pounds of fragile, pink crystals off the top of his salt ponds. The color will fade in the sun, and Bouleau will be left with the silvery and coveted fleur de sel.

Bouleau, 31, is a paludier, a maker of artisanal salt. Along the coast of northwestern France in the past few decades, paludiers --literally, marshers--have revived an ancient trade. In salt marshes there, they orchestrate the flow of seawater into a labyrinth of small, earth-dammed ponds And from the shallow pools at the center of the maze, some say, comes the best salt in the world.

It does not come easily. In December, Bouleau begins to clean out the maze. The outer ponds are coated with a variety of minerals, and those must be removed. Working toward the center, Bouleau scrapes away the residue to restore the bottom of his ponds to their original composition. "It's a very nice clay," he says, his Canada-born wife, Sylviane, translating.

In late spring or early summer, he opens the dams to let in the ocean. As the water slowly negotiates the maze, it evaporates and its salt content climbs. By the time it reaches Bouleau's 42 central oeillets (shallow ponds), the individual salt molecules are ready to link up. If the day is dry and windy, feathery crystals will begin to appear on the surface as salt-loving bacteria lend a pink cast to the thickening crystals. And the race is on to catch the fleur de sel, which is skimmed from the ponds with a long-handled wooden las (rake).

Bouleau says: "You have to get it in the late afternoon because at night the humidity makes the fleur de sel sink. Then it is lost."

Actually, it would not be a total loss. Bouleau's marsh produces 2,500 pounds of fleur de sel annually; but it also yields 126,000 pounds of sel gris (gray sea salt), which piles up on the bottom of the ponds. And this salt is worth a pretty penny, too.

It isn't every day that the fleur de sel must be harvested. It can be gathered only on days when the weather cooperates. Rain adds water to the ponds, setting back the process. Clouds impede evaporation. Windless days do, too. Some years, the harvest stretches from April to September. But other years, it lasts a month--or less.

"In 2000 we had an oil spill on the sea, so we didn't make any salt," Bouleau says. "And this year there was too much rain."

Which raises the question, Why would a person choose this particular profession in the first place? The skimming and carting of salt is physically demanding; the weather is nerve-racking; and the mosquitoes, on gentle summer evenings, are murderous.

"I think I know the answer to that," Sylviane says, laughing. "He went in the marshes when he was very small and has always liked them. He likes working in nature; he likes the sea; he likes working with the sand, the wind, the elements. Do you know what I mean?" she asks. "He doesn't like working at a desk. He likes to have his foot in the clay."

DIAGRAM: 1. A gate allows seawater into the marsh. 2. The flow slows as it enters the first basin, or vasiére. 3. The temperature of the water rises as it flows. 4. The salinity increases as the ponds become more shallow. 5. Salt is harvested from 1-centimeter-deep ponds knows as oeillets.

PHOTO (COLOR): Some say that fries are only vehicles for delivering salt.








PHOTO (COLOR): Harvesting the great salt flats of Utah sometime around 1910


By Hannah Holmes

Hannah Holmes is the author of The Secret Life of Dust (John Wiley and Sons, 2001).

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