Okay … I can’t seem to find if there’s necessarily any guidelines for labelling salt, but this is basically the types :
Table salt (or just salt) : Contains 99% or better purity Sodium Chloride. Often has Iodine added (in which case it will be labelled ‘Iodized salt’). The Iodine began being added in the 1920s to prevent goiter, a thryoid condition that results from lack of iodine. Is ground fairly fine to dissolve easily into food, as it is of course to be used at the table. Anti-caking agents are often added as well, and possibly dextrose to stabilize the iodine.
Kosher salt : named not for its ingredients but for its application, kosher salt could also be called ‘koshering salt’ to be used to remove blood from meat to make it kosher. Kosher salt is a bit larger grain and often more flaky than table salt, and is used to draw moisture out more quickly. Kosher salt usually has no additives like iodine.
Pickling or Canning salt : Again, pure sodium chloride. But has no iodine or anti-caking agent, and is usually a bit larger-grained than table salt (probably to prevent caking). The lack of additives is because it is for use in a brine (like pickles); the anti-caking agent will not dissolve in water and the iodine could cause a slight discoloration (probably not noticeable one, though).
Rock Salt : Largest-grained and still just Sodium Chloride. Rock salt is usually not added to food, but is used more for its chemical properties – most often to change freezing point of water (like on roads) or for use in water softeners.
Sea Salt : Basically the salt produced by solar evaporation before it gets to the refinery (or with little refinement). It usually contains 1-2% ‘other salts’ found in sea water, like Magnesium Chloride, Potassium Chloride, and Calcium Chloride. Definitely more variable in taste than the more refined salts, and a more distinctive taste as well, so it’s possible for ‘gourmet’ salts to be sold at a premium price. Some companies, apparently, do add iodine and other additives to the sea salt they sell as well.
If you have more questions about salt, you can get some answers from The Salt Institute. You should also see what comes up if you type http://www.salt.com into your browser.
Thanks, guys. I did a little checking myself in the Epicurious Dictionary, which says “[m]ost of today’s salt is mined and comes from large deposits left by dried salt lakes” and sea salt is “the result of the evaporation of sea water.” But then RealSalt says their product (for table use) is an “all natural sea salt…mined underground.” Eh, marketing doublespeak, or is there no time limit to how long ago the water evaporated?
Hrm… my handy chemistry book says only 10% of the world’s salt supply comes from evaporation, and that the other 90% is from halite mines. Is the western US just freakishly out of proportion (aside from the obvious)?
I think we all get enough iodine in our diets to avoid goiters now. Most of our processed food should contain enough iodine to keep us from turning into toads.
Salt ‘mining’ for table consumption generally involves drilling into a salt deposit, pumping hot water down into it, and then collecting the brine as it comes up. The brine is then evaporated. This is the sort you eat. There are, however, about ten million non-dietary uses for salt, to which the 90% actually dug from the ground is put to.
The Jurassic Louann Salt is a widespread evaporite that extends from Texas (actually, I believe it is present in Mexico as well), across southern Arkansas, Louisiana, Mississippi and western Alabama. It extends about 100 miles out into the Gulf of Mexico; some think it once covered the entire Gulf area (which was a small basin then).
Salt has a plasticity that allows columns of it intrude to the surface in response to the weight of the overlying rock layers, the intrusions are in the form of salt domes and ridges, and the domes come quite close to the surface even when the original Louann is 2 to 4 miles below. All of this salt could be called sea salt, as it is the result of evaporation of an epeiric sea.
Salt is mined at salt domes. I don’t know much about the salt business, but I do know Cargill mines salt at the Avery Island Dome and Morton’s mines salt at the Weeks Island Dome, both within spittin’ distance of each other in South Louisiana.
The brine mining method Trucido mentions is used along with a “room and pillar” method where they mine but leave large pillars to support the internal structure of the dome.
No it isn’t. Go get packets of salt from various fast food places, especially the national chains like McD’s and Burger King that package their own condiments. Go read the labels. You will be very surprised at the ingredients in this “salt.” I’ve found potassium salts (a common salt substitute) and even MSG. Burger King even adds dextrose to their salt. What the hell is sugar doing in the salt?
I’ve only found one instance where the store brand is inferior to the name brand it’s supposed to be imitating. The Kroger store brand fiber supplement is packaged similarly to metamucil, and does contain the same active ingredient - but the recomended dose for the Kroger brand is 1 tablespoon in an 8 oz. glass of water, 2 or 3 times a day. Metamucil is one teaspoon in an 8 oz. glass of water, 1 or 2 times a day. The Kroger brand is grittier and has dark flecks in it, while Metamucil is smooth and homogenous. The Kroger brand is sweetened by sugar, while Metamucil has aspartame.
Iodine deficiency is no joke. In many parts of China (eg Gansu Province) entire districts are inhabited by generations of mentally retarded people because of a lack of iodine in the soil. Programs to distribute iodized salt are a big deal in these places.
But don’t use it for pickling onions. Sea salt is great - but here in humid Hong Kong it turns into lumps of wet white crystal within days.
Ahh, many people who know much about food preperation would love to chime in here and tell you all about salt. I’ve tasted meat that was meaningless with one salt, and heaven with another.
Now, maybe the “Morton vs. Store Brand Challenge” isn’t that dramatic, but anyone with any knowledge of how various salts could affect a meal wouldn’t discount the impact of using one salt over another.