Pickling salt, also known as canning salt, is commonly used when pickling and canning vegetables like pickles. Pickling salt is similar in appearance to regular table salt except it does not contain any iodine or anti-caking agents that are normally added to salt. Neither of the two additives is harmful to the canning process, but they are known to produce a visually unappealing product. Iodine can turn pickled vegetables dark and unappetizing and the anti-caking agent, commonly sodium silicate or tricalcium phosphate, can turn the pickling brine cloudy.
This salt can be found in the canning section of many supermarkets, especially in rural areas. It can serve as a substitute for regular salt in most recipes. However, because pickling salt does not contain any anti-caking agents it can form clumps on humid days. These clumps can be removed by drying out the salt in a warm oven.
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