4.1 Salt and sodium
Types of Salt
Salt1 can be found deposited in Earth’s layers in rock salt deposits. These deposits formed when the water in the oceans that covered Earth many millions of years ago evaporated. The salt was then covered by various types of rocks. Today, there are three basic methods of obtaining salt from natural sources:
- Mining rock salt
- Extracting salt from salt brines created by pumping water into underground salt deposits
- Evaporating saltwater from oceans, seas, and salt lakes
All salt, whether mined or evaporated from seawater, originates from seawater and is mostly made up of sodium chloride. Taste is determined by the size and shape of the salt crystals and the amounts and types of minerals present. Some types of salt include:
Table salt: typically mined salt, refined, bleached with no trace elements, small crystals that most recipes are written for. This type of salt is also available iodized.
Sea salt: evaporated from the ocean water, typically has a small amount of iodine, both fine and coarse varieties.
Mined culinary salts: available in many different colors, as they contain small amounts of minerals from where they were mined, such as the Himalayas (pink) or Celtic (grey) regions.
Kosher salt: used to prepare foods according to Jewish dietary practices, provides a coarse texture to cook with, and is less likely to contain additives.
Minerals in Salt
There are some nutritional differences in types of salts that result from the processing of salt. Unrefined salt is in a more natural state and therefore contains minerals from where the salt was mined, while refined salt does not. In addition to providing a small nutrient boost, the use of unrefined sea salts may taste different due to the minerals present.
Iodine is a mineral important for thyroid function and is present in very small amounts in sea salts. An adequate intake of iodine may be difficult to achieve in areas that are far from the ocean, as most iodine is present in or near the ocean. For this reason, iodized salts are available to consumers in order to prevent iodine deficiencies that could lead to goiters, hypothyroidism, and brain damage.
Where is Sodium found in the Diet?
Sodium is present in small amounts in fruits, vegetables, and grains. Home cooks add sodium to foods during cooking and people use the salt shaker at meals. High amounts of sodium are often found in processed foods, such as canned soups and luncheon meats.
Bread is another major source of sodium in the diet, as sodium is used not only as a flavor enhancer but also acts as a preservative. In addition, sodium slows the growth of yeast2 (a fungus that makes bread rise) in yeast-leavened products. It also strengthens the structure made from gluten, which is what makes bread flexible and springy.
FOOTNOTES
1 Salt
2 Sodium slows the growth of yeast