Japanese sea salt

[Nargi]

So I've asked around, looked things up, racked my brain to no avail. I have a number of different salts in my culinary repertoire, and something I've discovered is that the majority of salts (sea salts, generally) from Japan that I see are in sold in a bag and have the consistency of wet sand. Anyone know why this is? Why not just remove the moisture? Is there any distinct advantage over dry salts?

note: some sel de gris is the same way.

[_john]

I think it is nigari solution? just a guess

[helenjp]

Yaki-shio, or dry flaked salt that has been dried over (high) artificial heat, is also available, but is really only used for sprinkling or as a condiment.

The coarse, wet salt that we see does (ideally) contain more than just sodium chloride. It usually contains magnesium chloride, and other minerals (as John says, the type that are found in nigari).

I always heard that this type of salt dissolves more readily, but when I googled in Japanese, I found an explanation that maybe makes more sense - heating converts some into an insoluble form...so I guess the wetter salt IS more soluble, not just because it's in a wetter form, but because it's chemically different in some aspects.

Now somebody should come along and prove me wrong!

[Batard]

Since Japan has no known rock-salt deposits or other terrestrial salt sources, they produce all their salt from evaporation of seawater. So traditionally their production method is different; it is crystallized in wooden bowls in solar houses. I am not sure why they don't dry it all the way out, maybe they feel it loses something if all the moisture is removed.

[Hiroyuki]

My findings are:

Magnesium chloride absorbs moisture in the air, which makes the salt wet. Roasting wet salt will make and keep it dry because the magnesium chloride is thermally decomposed by roasting.

[Nargi]

Nice. All of those things are totally valid and useful. Thanks for all the information; now I get to impress some Japanophiles I know.