Free What Einstein Told His Cook by Robert L. Wolke Page A

where it came from . You can’t generalize. Thus, when a recipe specifies simply “sea salt,” it is a meaningless specification. It might as well be specifying “meat.”
    ADDITIVES
     
    Sea salt is often specified to avoid the “harsh-flavored additives” in shaker salt. Whether from a mine or a sea, shaker salt does indeed contain anti-caking additives to keep its grains flowing smoothly, because they are tiny cubes and their flat surfaces tend to stick together. But the FDA limits the total amount of all additives to a maximum of 2 percent, and it is invariably much less than that. Morton’s table salt, for example, is more than 99.1 percent pure sodium chloride and contains only 0.2 to 0.7 percent of the anti-caking agent calcium silicate. Because calcium silicate (and all the other anti-caking agents) are insoluble in water, shaker salt makes a slightly cloudy solution.
    Other common anti-caking additives are magnesium carbonate, calcium carbonate, calcium phosphates, and sodium aluminum silicates. These are all completely tasteless and odorless chemicals.
    But even if they weren’t, even if expert tasters could detect subtle flavor differences among solid salts due to an additive of less than one percent, the 50,000-fold dilution factor that occurs when the salt is used in a recipe would certainly wipe them out. Just do the math. One percent of a 6-gram teaspoon of salt is 0.06 gram of additive in 3 quarts or more than 3,000 grams of stew: 3,000 ÷0.06 = 50,000.
    FLAVOR
     
    There is no denying that some of the finer (read more expensive) sea salts—even below the boutique level—have interesting flavor characteristics. But that depends on how they are used and on what your definition of “flavor” is.
    A food’s flavor consists of three components: taste, smell, and texture. With salt, we can pretty much eliminate smell because neither sodium chloride nor the calcium and magnesium sulfates that may be present in some of the less purified sea salts have any odor. (Techspeak: They have exceedingly low vapor pressures.) Nevertheless, our sense of smell is very sensitive, and it is possible that a smell of algae in these less purified salts might be detected. Also, when any kind of salt is inhaled nasally as a fine dust, some people report a slight metallic sensation high in the nose.
    That leaves taste and texture: what the taste buds actually detect and how the salt feels in the mouth.
    Depending on how they were harvested and processed, the crystals of different brands of sea salt can vary widely in shape, from flakes to pyramids to clusters of irregular, jagged fragments. (Check them out with a magnifying glass.) The sizes of the crystals also can range from fine to coarse, although virtually all of them are coarser than shaker salt.
    When sprinkled on a relatively dry food such as a slice of tomato just before serving, the bigger, flakier crystals can deliver bright little explosions of saltiness as they hit the tongue and dissolve or as they are crushed between the teeth. That’s why the savviest chefs value them: for those sensuous little bursts of saltiness. Shaker salt doesn’t do that because its compact little cubes dissolve on the tongue much more slowly. Thus, it is the complex shapes of the crystals, not their nautical origin, that give many sea salts their sensory properties.
    The reason that most sea salts have large, irregularly shaped crystals is that that’s what slow evaporation produces, whereas the rapid vacuum-evaporation process used in making shaker salt produces tiny, regularly shaped grains designed to fit through the holes in the shaker. That’s a phenomenon well known to chemists; the more rapidly crystals grow, the smaller they will be.
    COOKING
     
    Crystal size and shape are irrelevant when a salt is used in cooking, because the crystals dissolve and disappear completely in the food juices. And once dissolved, all textural differences are gone. The food doesn’t know what