In making nigari, crystals form in the following order:
- Calcium sulfate (gypsum)
- Sodium chloride
- Magnesium sulfate
- Magnesium chloride
- Potassium chloride
The different ways of making nigari
Sun dried (natural nigari)
Natural nigari taken from the time-honored process of making salt by putting seawater into a saltpan and letting it dry in the sun. Nigari made by this process still contains large amounts of magnesium sulfate and hence has a very bitter taste. Nigari produced by this process is almost all non-Japanese.
Kettle-boiled (natural nigari)
Natural nigari taken from the water on top of the sodium that crystallizes on the bottom when seawater is boiled down in a large kettle. Almost all the nigari in Japan is produced by this method.
A process used in the making of deep ocean water.
When changing seawater to freshwater the “reverse osmosis” filter is used. With this reverse osmosis filter all the mineral elements as well as the impurities contained in seawater are removed, making this close to pure fresh water. The nigari taken from the reverse osmosis filter is added to this pure water, making deep ocean water. In other words, nigari water.
But this nigari, made from the reverse osmosis filter, is condensed seawater and is extremely high in salt (sodium) content. Rather than call it nigari, isn’t this just concentrated sea water, or strong saline? Basically nigari ought to be a solution of condensed seawater with the sodium largely removed, so that the sodium content is 1/5th of the magnesium content. The companies using this type of nigari cannot get it in large amounts so almost all of them either dilute it with water or adjust it by adding powdered magnesium. The right balance of minerals is very important for natural nigari.