The process of producing a popular condiment
Salt is an essential mineral used as a seasoning, preservative and chemical, providing for billions of consumers around the globe. ⬤ How does salt come from the earth and reach your table? The process of collecting and manufacturing salt, and its different variations, is more complicated than you might think.
Where does salt come from?
Salt, or sodium chloride, is a mineral that is usually produced from natural resources. There are several ways to produce salt forms, and those methods have evolved over time. Where and how it’s produced depend on the type of salt being manufactured.
In 2022, the United States produced 42 million tons of salt, valued at around $2.5 billion, the U.S. Geological Survey, Mineral Commodity Summaries reported. Salt made from brine is largely produced in Kansas, Louisiana, Michigan, New York, Ohio and Texas. Evaporation processing facilities for salt production primarily are in Arizona, California, Nevada, New Mexico, Oklahoma and Utah.
In 2021, the United States was the eighth-largest exporter of salt in the world, and its biggest clients were Canada, China, Germany, Mexico and Belgium, according to the Observatory of Economic Complexity.
How is salt made?
Salt is made via several common methods: mining, evaporating seawater or brines and using artificial heat.
Mining: Naturally grown rock salt is mined from salt deposits in the earth using common excavation tools and methods. This allows for the highest degree of salt purity, and producers can refine these harvests or sell them.
Most commonly, these large clumps that are freshly mined from the deposits are crushed, ground into various sizes and then sorted for distribution.
⬤ Evaporating: Seawater and brines – highly concentrated salt water that may naturally occur underground or in salt lakes – are the most common sources for evaporating salt. The tools used to evaporate seawater or brine depend on a country’s climate and rainfall, but most countries follow a similar process. First, the liquid runs through a series of wood filters to separate any impurities from the liquid. Then, the filtered liquid is run through several crystallizing pans that cool the liquid to a temperature that forms ice that separates from the salt. This process is repeated until only the solid mineral is left; harvesters rake it into rows and allow the excess liquid to drain for days. The salt is collected and drained more to be sorted and distributed.
⬤ Artificial heat: Brine or other kinds of salt water are placed in a vacuum vessel that has enough pressure to boil the liquid. Depending on the kind of salt shape the producer is making, the weight of pressure will vary.
Where does salt in the ocean come from?
The saltiness of the ocean comes from several places: runoff from land, salt domes, underwater vents that release hydrothermal fluids and underwater volcanoes that send minerals into the water, according to National Oceanic and Atmospheric Administration.
About 3.5% of the ocean’s weight comes from dissolved salts alone. Sodium and chloride comprise about 85% of dissolved ions in the ocean.