Chemically there are many types of salts, the ones used in cheese making are common household eating salt, a mineral composed primarily of Sodium Chloride (chemical abbreviation is NaCl) and is essential for human and animal life. Salt is usually produced from evaporating sea water or by mining ancient seabed rock deposits. It is manufactured into different forms:
- Raw sea salt which is bitter due to magnesium and calcium compounds and thus is rarely eaten. These are common in bathing additives and cosmetic products.
- Refined salt which is ~99% Sodium Chloride.
- Refined flourinated and/or iodized and/or anticaking salt.
Flourinated salt is manufactured in some countries to promote dental health. The effect of this type of salt used in making cheese is unknown.
Iodized or iodised salt is regular crystalline NaCl salt mixed with a minute amount of various iodine-containing salts such as potassium iodide, sodium iodide, or sodium iodate. Many commercially manufactured table type salts are iodized to help prevent iodine deficient diseases in humans such as mental retardation and thyroid gland problems such as goiter.
However, iodine also will retard or kill the growth of the cultures in cheese and thus should not be used in making cheese.
This can be an issue in some countries where all manufactured table salt is iodized by law. However often in those countries special non-iodized “canning and pickling” salt is often manufactured for making brine used in pickling vegetables as iodine can be oxidized by the foods and darken them.
Many manufactured salts are anticaking and are often labeled as “Free Flowing” or “Table Salt” as they are made with NaCl salt and anticaking ingredients such as sodium aluminosilicate, sodium ferrocyanide, potassium ferrocyanide, calcium carbonate, or magnesium carbonate. These additives prevent the formation of lumps caused by moisture “melting” salt crystals together and thus provide easier packaging, transportation, and consumption.
Some anticaking agents are soluble in water; others are soluble in alcohols or other organic solvents. They function either by absorbing excess moisture, or by coating particles and making them water-repellent, calcium silicate, adsorbs both water and oil. Anticaking agents are also commonly used in manufactured cake mixes, powdered sugar, non-dairy creamers, dry cheese products, and many other dry mixes.
Because of the properties listed above, anticaking salts should not be used in direct salting cheese as they can affect the moisture content of cheeses and/or the dissolution of salt in the cheese. However they can be used in brines where the intent is to imbibe salt into the cheese and to dehydrate the surface to build a cheese rind.
Common retail grocery store food grade dry salts that can be used in making cheese are:
- Regular salt, if non-iodized and no anticaking additives.
- Canning or Pickling Salt which normally is non-iodized and no anticaking additives and is manufactured fine-grained to accelerate its dissolution when making brine.
- Rock or Kosher Salt, which is large crystal normally non-iodized and no anticaking additive.
- Food grade swimming pool or water softener salt for brines as as large size pellets.
- Flaked flat crystal salt normally non-iodized and no anticaking additive which packs lighter than common sand crystal type salt, melts easily, and does not easily bind together. Sometimes called “cheese salt” and is often not readily available in grocery stores. Note, there is no advantage to this salt when used to make brine.