Everything You Wanted to Know About Salt but Were Too Afraid to Ask

I’m not being hyperbolic when I say salt is the most important seasoning of all time. It makes things taste salty, sure, but it also makes things taste like better versions the themselves, and more importantly, salt is a powerful preservative and natural anti-microbial. Long before refrigeration—all the way back to ancient Egypt—salt kept meat from spoiling which, in turn, kept people fed longer. And though salty processed foods don’t have the best reputation, sodium is an essential nutrient, needed to keep your fluids balanced and muscles and nerves working smoothly. Salt is important.

We don’t live in ancient Egypt, and it’s currently quite easy to keep your electrolytes where they need to be for normal brain and bodily functions. So while the modern eater may be a little blasé about salt, flavor is not trivial. Chef-y types have strong opinions about brands and crystal size (and so do I), but the salt you stock your kitchen with should be the salt that fits your culinary needs.

Here’s what you need to know about salt, from the standard iodized table variety to the various Kosher offerings.

What is salt?

Let’s start out simple. What we refer to as “salt” is sodium chloride. More broadly, a salt is a chemical compound comprised of a positively charged ion and a negatively charged ion. Culinary salt is a halide, most commonly made of a positively charged sodium ion and negatively charged chloride halogen in a one-to-one ratio, though potassium chloride is sometimes mixed in to lower the sodium content. (Potassium chloride tastes pretty bitter, and not at all “salty” on its own, however, and is mostly added for bulk.)

The sodium is what gives salt its flavor, but pure sodium is an unstable, highly reactive metal that is not readily found in nature, so the ionized form attaches itself to negatively charged ions to make a stable salt. (Seasoning a pot of soup with pure sodium would be a disaster; it reacts violently with water.)

What is iodized salt?

Iodized salt or table salt is the most the most common, or at least the most widely recognized form of culinary salt. “Table salt” may sound like whatever form of seasoning you wish to use at your table, but the term refers to highly refined salt with a small crystal size that flows easily from a salt shaker. Table salt (and therefore iodized salt) is mined from underground deposits, then processed to remove other minerals, before being fortified with iodine.

Iodized salt is made by spraying sodium chloride with a small amount of a potassium iodate or potassium iodide solution to combat iodine deficiency, a global health issue that can lead to metabolic issues like goiter, thyroid issues, and congenital birth defects. Some people think iodized salt tastes bitter when compared to pure sodium chloride, but you would have to have a pretty sensitive palate to taste the difference, especially in small quantities.

Iodized salt has a small, compact, uniform crystal size, which allows you to really pack in the sodium and is why it tastes “saltier” than kosher salt and sea salt, ounce for ounce.

What is sea salt?

There are two places you can find salt: the ground and the ocean. Sea salt is sodium chloride that comes from the ocean or other salty bodies of water. It’s made by letting the briney water evaporate, leaving behind sodium chloride crystals, along with some other minerals and impurities. It’s less processed than table salt, and hippies and marketers are both fond of branding sea salt as “better” for you, though there is no real science to support that. (In fact, iodized salt can be a real life saver in places where other iodine-rich foods aren’t available.)

The flavor and color of sea salt can vary, depending on what other minerals were hanging out in the body of water it came from. It has a larger, more irregularly shaped crystal than table salt, which is why some people claim it tastes “less salty”—a teaspoon of sea salt contains less sodium than a teaspoon of table salt.

What is kosher salt?

Kosher salt is not salt that has been blessed by a rabbi, nor does it come from special salt mines or holy seas. It got its name from its use in the koshering process, where it is used to draw blood out of meat. This is different from “kosher certified salt,” which is mined, processed, and packaged under strict Jewish guidelines.

Kosher salt is valued for its coarse, large crystal and pure flavor, though some are more pure (and prized) than others. There are two big brands of “kosher salt”—Morton Kosher Salt and Diamond Kosher Salt, and they are not interchangeable. According to Samin Nosrat, the processes used to make them could not be more different:

There are two major producers of kosher salt: Diamond Crystal, which crystallizes in an open container of brine, yielding light and hollow flakes; and Morton, which is made by rolling cubic crystals of vacuum-evaporated salt into thin dense flakes.

You may think that flakes are flakes, but the shape of the flakes makes a huge difference. Thin sheets lay flat, letting you pack more sodium chloride in any given volume, while Diamond’s pyramid-shaped crystals align a little more chaotically, and take up more space in the measuring spoon. The denser Morton crystals also take a little longer to dissolve.

Out of all the salts I have in my kitchen (and I have a lot), Diamond Kosher Salt is by far the “least salty,” in that I have to use a larger volume of it to achieve the same levels of salinity. (It is, however, pure sodium chloride, unlike Morton, which contains anti-caking agents.)

All of this makes Diamond a great cooking salt for beginner cooks, as the danger of over-salting is near zero. Not only are the fluffy flakes easy to sprinkle, their quicker dissolve time means you get a truer, faster understanding of how salty your dish is, as you won’t have any undissolved granules lurking around, waiting to surprise you later. It’s also “grippier” than the flat Morton flakes, so it sticks to meats and the like a little bit better.

All that being said, using Morton salt will not ruin a meal. If your recipe calls for one over the other, it is easiest to use the specified salt, but you can convert from between salts if you know their mass (and I do).

How to convert between types of salt

Sodium chloride is sodium chloride but, as I’ve discussed ad nauseum, crystal size and shape make a big difference when measuring salt by volume, which is why it’s better to think of the mass of salt you’re using in a recipe, rather than the number of teaspoons.

According to America’s Test Kitchen, a tablespoon of Morton Kosher Salt weighs 16 grams, a tablespoon of Diamond Kosher Salt weighs 10 grams, and a tablespoon of “standard” table salt weighs 23 grams. Those are big differences. If a recipe calls for 1 teaspoon of Morton, and all you have is Diamond, you can find the needed measurement by multiplying it by 1.6, since we know you need 1.6 times the volume of Diamond to get the same amount of sodium chloride by mass.

That’s easy, because 10 is an easy number to work with. For more complex conversions, like table salt to Morton salt, you might want to reach out to my old school chum, dimensional analysis. For example, if your recipe calls for 2 teaspoons of table salt, but all you have is Morton, you could calculate it like so:

2 teaspoons table salt x (1 tablespoon/3 teaspoons) x (23 grams NaCl/teaspoon table salt) x (1 tablespoon Morton/16 grams NaCl) x (3 teaspoons/1 tablespoon) = 2.87 teaspoons Morton salt, which you would round to 3 teaspoons

Calculating it this way helps you ensure all the units cancel out, so you know you are calculating the right thing. (You are of course welcome to use whatever math you like, but dimensional analysis has never failed me when converting measurements.)

Other miscellaneous salts you might encounter

Table salt, sea salt, and kosher salt are the big three, but you can buy sodium chloride in a wide variety of shapes and colors. Maldon salt, for instance, is a “finishing salt,” with huge, pyramid-shaped crystals. It would be a terrible cooking salt—you would need so much of it—but it provides a fun textural element when sprinkled on at the last moment (you can also get a smoked version).

Fleur de sel is a French finishing sea salt, made by letting salty water evaporate into flakes so delicate, they are traditionally harvested by women (which the French consider to be “the more delicate sex”). Do not cook with fleur de sel; it’s too expensive, and doing so will obliterate the delightful texture.

Then there are the colorful salts, pink salt and sel gris being the most popular. Pink Himalayan salt is mined from Khewra Salt Mine, near the Himalayas in Pakistan. It is minimally processed and unrefined, and gets its pink color from naturally occurring minerals, particularly iron. You can buy it in a wide variety of shapes and sizes—including shot glasses and big ol’ blocks—but it is most commonly used as a table salt. (If you want to cook with it, weigh a tablespoon of it, then convert as need as described above.)

“Sel gris” is French for “grey salt,” because it is salt that is grey. Like fleur de sel, it is harvested from salty waters, and it gets its color from contact with the evaporating pan. According to Mark Bitterman’s Salted: A Manifesto on the World’s Most Essential Mineral, With Recipes, it is a moist salt, usually retaining around 13% residual moisture. This makes it a poor choice for dry brining, curing, or any other culinary application where the salt is meant to draw moisture from the meat, but it does have a richer, earthier flavor than refined salt.

There are other colors of salt, including black and red, but I think you get the point. Color indicates impurities, usually minerals, though flavored salts (like pinot noir salt) also take on the coloring of their flavoring agents.

Then you have pickling salt, a pure sodium chloride which is finer than even sea salt. You can use any pure salt to pickle, though pickling salt dissolves like a dream. (When converting salt measurements for pickling recipes, use the University of Wisconsin-approved ratio of 1-1/2 cups of flaked kosher salt for every cup of pickling salt.)

Ice cream salt is not edible, and should not be put in or on ice cream. It is a rock salt used in ice cream making, where it helps the ice and water drop to sub-freezing temperatures through a little thing known as “freezing point depression.” It is not food grade, but it is sodium chloride, and if you were to lick it (which you should not), it would taste salty.

This is by no means a complete list of every type of salt you can buy and use, but it should be enough to get you started. Most kitchens do not need more than one or two types of salt. Morton Kosher is a good beginner all-purpose salt—and it’s great for dry brining—but I always have a bucket of Maldon around for finishing (and snacking on), and I like to keep a fine sea salt on hand for cooking (I like my food seasoned, and Morton is just not “salty” enough for my needs.) Also, don’t let the snobs tell you there is anything wrong with plain old table salt. It’s cheap, it’s salty, and using it ensures there’s always plenty of iodine in your diet.

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