So you're ready to do some pickling or fermenting and the recipe calls for "pickling salt." What makes pickling salt special, and can you substitute another kind of salt? Here's the scoop...
Pickling salt — sometimes called canning salt or preserving salt — is pure granulated salt (sodium chloride). Unlike table salt, pickling salt does not contain anti-caking ingredients, which can turn pickles cloudy, or additives like iodine, which can make pickles dark. In addition, fine granules make pickling salt easy to dissolve in a brine. Morton and Ball are two common brands available at grocery stores.
Although table salt is perfectly safe to use in pickling, it is not recommended because the quality of pickles may suffer. Kosher salt is a better alternative, as long as it is pure salt without any additives. (Diamond Crystal is a good brand; avoid Morton, which does contain anti-caking agents.) Pure sea salt can also be used in pickling.
When making salt substitutions, keep in mind that weight per volume can differ. Coarser salts may also take longer to dissolve. The University of Wisconsin - Cooperative Extension advises that 1 1/2 cups of flaked kosher salt equals about 1 cup of canning and pickling salt. For fermented pickles, they recommend measuring by weight: 7 3/4 ounces (220 grams) of flaked salt is equivalent to 1 cup of canning and pickling salt.