A question I get asked a lot is, "kosher salt versus sea salt?" The latter two terms are often used interchangeably. However, they are not the same thing and are used differently for each type of salt. Here's the difference between kosher salt and sea salt.
A: In a word, yes, they are similar. Kosher and sea salt both have the mineral content, which is primarily sodium chloride, from the earth. By molecular weight, both three have the same volume of sodium chloride in them. So, by weight, all three have about the same amount of sodium chloride in them. This is the biggest difference between the two.
B: There are several differences in the molecular structure of kosher salt and sea salt, which affects their properties when they are used in food preparation. Sea salt is more abundant with trace minerals, which gives it a more varied sensory experience. Table salt is less varied and more concentrated with sodium chloride. So the two forms are used to salt certain foods, however, the one that is closer to the "normal" table salt is more regulated and more expensive. Also, the taste of kosher salt is somewhat saltier than sea salt.
C: Sea salt is naturally blemish-resistant and tends to be neutralized by the effects of the sun. Because of this, it tends to take on a grayish color when it is exposed to sunlight for long periods of time. In contrast, kosher salt tends to take on a more yellowish color, which is good for cooking and baking. This is a difference that most people will notice only after they have used sea salt on a regular basis.
D: There are three types of grains that kosher salt is made from. Regular kosher salt is made from unprocessed kosher salt, which has been ground down and then ionized so that it can absorb more moisture. It is a fine seasoning salt for use in a wide range of cuisines. However, not many processed grains are used in the salt mines, due to their pore-clogging properties.
E: Knez kosher salt is generally a coarser, greyish-white powder that is easily recognized by its somewhat coarse texture. It is often combined with table salt or other cooking ingredients for a garnish. It is also sometimes used as a substitute for regular table salt, especially in the United States. However, there is no need to substitute regular table salt for it, as it does not have the pore-clogging effects of sea salt and it is less expensive. It is the only salt that can be found in the Dead Sea, a legendary mineral pool whose salts are re-purposed as salt for use in Israel.
F: As its name implies, kefir is a fermented milk beverage. The term is an evolution of the term "kefir," meaning "dried milk," which was the liquid left over after making cheesecake. The term was first used in ancient Babylonia, the first country to produce kefir. The grains in kosher salt have a coarse texture, similar to sea salt, yet it is usually less absorbent than regular table salt and can add much needed moisture to soups and stews.
G: The main difference between kosher salt and regular salt is the way they're processed. Kosher salt is created via a slow process, which allows for smaller particles to be included in the salt creation process. This, in turn, makes the salt healthier for your digestive system and your body. Sea salt is mass-processed, causing its particles to be very large and its shelf life to be shortened.