Seaweed

[torakris]

Salted seaweed needs to be washed well and then soaked to rid it of the excess salt. Wash it well under running water sort of rubbing it together, then soak it in water for 15 to 20 minutes. Taste it to see if it is too salty, occasionally it might need to be rubbed under the water a liittle more.

It is now ready to be used, it can be added to soups, made into salds, it is even good in quick stirfries.

I love seaweeds salads, I mix a couple of varieties of seawed together and then dress it with a simple "wafu" (Japanese style dressing) made with oil, soy sauce and rice vinegar and embellished with what ever I am feeling like at the moment. Maybe a couple drops of sesame oil and some freshyly toasted and crushed sesame seeds, of some smashed up umeboshi (pickled plums), or maybe with a lot of shredded shiso and maybe some myoga or ginger as well.

[Hiroyuki]

My wife and I seldom buy salted wakame partly because of its high price, but we sometimes make a simple salad with dry wakame and enoki mushrooms.

Dressing that we use with this salad:

Soy sause : Vinegar : Sesame seed oil = 1 : 1 : 0.5

[Aix]

Thank you both.

I rinsed the seaweed in 2-3 changes of water and didn't find that it required much soaking as it was not salty at all. I haven't made salad yet; I used it in miso soup. It was amazing. What a beautiful food... great texture too.

Regarding the price: my small bag of salted seaweed cost me C$2.99 and will give me five times the yield of the $5 bags of dried seaweed. Go figure the fresh stuff would be cheaper up here.

[Aix]

What seaweed is usually used in the ubiquitous green seaweed salad you find in Japanese restaurants? It looks like a much brighter green seaweed, with a few clear strands. It's not as flat as wakame either. Any idea?

[Hiroyuki]

There is a tip: Wakame turns to green as soon as you put it in boiling hot water. Then, you have to put it in cold water immediately. This way, wakeme retains its vidid green.

[helenjp]

Interesting!

My husband comes from Hokkaido, and although he's extremely stingy about spending more than necessary on food, he wouldn't consider buying dried wakame, and is quite the connoisseur on different types of salted wakame.

A friend brought me back some ash-dried wakame from her home-town. It was nice, but it was quite a chore washing the ash off every time I wanted to use some.

[Aix]

Just curious: how do you cut wakame for salad? In julienne or ribbons? Most seaweed salads I see in restaurants are shredded rather thin but with wakame it's a bit too slimy to get a true fine cut...

[helenjp]

Wakame does vary a little bit -- the better grades expand to quite wide fronds with a certain thickness to them, while the cheap ones are very thin and tatty.

Normally you soak the fronds, then cut or tear off the fine whiteish "stem" that runs along one side of each frond. Then fold the fronds up and slice finely. If you do this before they have fully expanded, and then toss the shredded wakame back into the water to finish soaking, it is easier to handle than waiting until the wakame is fully reconstituted.

[torakris]

with the cheaper wakame it can be difficult to shred so I just leave it in bite size pieces, like the size you see floating in miso soup.

[Hiroyuki]

This is the wakame I usually buy at the local store. This bag, which contains 100-g dried wakame, costs only 198 yen. Quite reasonable. That's why I like it. The bag says that the wakame will increase 15-fold. How about that!

[giantbee]

I tried making wakame salad recently using the refrigerated salted type, and followed the recipe directions to cook it briefly and cool it before adding the seasonings. I found the result a bit too soft and slimy. Is it customary to boil wakame prior to making a salad with it? I've never had it before so perhaps it had the appropriate texture after all.

Anne

[torakris]

I tried making wakame salad recently using the refrigerated salted type, and followed the recipe directions to cook it briefly and cool it before adding the seasonings. I found the result a bit too soft and slimy. Is it customary to boil wakame prior to making a salad with it? I've never had it before so perhaps it had the appropriate texture after all.

Anne

There is no need to boil salted wakame. You can washi it and place it in a strainer and pour boiling water over it and washi it again or you could wash it and place it in a bowl of water for 5 to 10 minutes and then wash until the saltiness is either gone or to your taste.

[Cephalopunk]

Last night, I had a nice piece of broiled mackerel (saba, ne?) with a cold hijiki salad; it reminded me of how much I enjoy hijiki. This particular salad was sprinkled with sesame seeds and had another taste similar to tahini - possibly black sesame paste? I found organic bulk, dried hijiki with other seaweeds (Kombu, Dulse) for $25 per pound. Admittedly, the store was in Manhattan, but this price discourages me from just fooling around. Any information that you have on preparing hijiki would be extremely helpful.

Sidenote: My girlfriend is a vegan; hijiki may be a good way to work in B12 and Iron.

[Cephalopunk]

Uggh, why do I feel I can't win sometimes?

[torakris]

Uggh, why do I feel I can't win sometimes?

wow, that's scary!

I love hijiki and actually eat it quite a bit....

I will post recipes anyway in just a bit.

[Hiroyuki]

What I found is this PDF file:

http://support.spring8.or.jp/training/text/031127/envi_4.pdf

(Japanese only)

An excerpt, together with a translation (by me):

天然海産物であるひじきには100g 当たり約 20mg ものヒ素が含まれている。ひじき中のヒ素はヒ素糖と呼ばれる無毒の化合物を形成して存在しているから食べても問題ない。

Hijiki, natural seafood, contains as much as 20-mg arsenic per 100g. The arsenic in hijiki exists in the form of a harmless compound called arsenic sugar* and, therefore, eating it does not present any problems.

* Literal translation; I don't know the technical term for it in English.

[johnnyd]

FYI:

The Canadian link was last modified over two years ago.

I respect the Canadian findings but since I just bought a bag of it I guess I'll limit consumption but not elliminate it altogether, it's too delicious. Looking forward to those recipes. I usually add red pepper, sliced in my mandoline, sesame oil w/mirin and rice vinegar, but I'm eager for variations.

[Hiroyuki]

I made an inquiry to that agency about the toxicity of hijiki, and they have just sent me the following reply:

The advice issued in the information bulletin posted at

http://www.inspection.gc.ca/english/corpaf...0011029be.shtml

remains in effect as no reduction in inorganic arsenic levels in hijiki seaweed has been reported.

Thank you for using the CFIA web site.

EDIT:

And another just now:

The advice issued in the information bulletin posted at

http://www.inspection.gc.ca/english/corpaf...0011029be.shtml and later published as a fact sheet at

http://www.inspection.gc.ca/english/corpaf.../arsenice.shtml

remains in effect as no reduction in inorganic arsenic levels in hijiki seaweed has been reported.

Thank you for using the CFIA web site.

Edited June 22, 2004 by Hiroyuki (log)

[smallworld]

I asked my Dad (AKA Mr. Science Man) about this and here is what he had to say:

About arsenic and hijiki- it's been fairly well studied, mainly by

researchers in Japan (Kyoto Univ among others) but as far as I can see,

only Canada's CFIA has issued a warning. None of the documents I could

find on the Websites for various chemistry and food journals provided

actual data which would allow one to compare the levels of different forms

of arsenic in Hijiki to those in other foods known to contain As (like

cashews, Brazils and othet nuts, as well as most shellfish), but the

cosistent finding is that hijiki has higher levels of inorganic As- as

you pointed out in your email.

Inorganic As is more toxic than organic forms.  Given that hijiki has

relatively high levels, I think it's prudent to avoid eating it, at

least until we can understand it- and the real risks- better.  Arsenic is

an odd mineral- there's increasing evidence that a tiny amount may be

essential to good health, but just a little bit more might be quite

harmful. Selenium is also like this. The form of As found in shellfish and

finfish is arsenic-betaine, which is very rapidly eliminated.

Inorganic arsenic can linger a little longer, and aside from

accumulating in hair and nails, it also can accumulate in the liver.  It does not

go into body fat, but like mercury, it seems to bind to protein matter

(muscles, skin, hair, nails).  Hijiki is a plant that appears to have

the ability to naturally accumulate As in its stems and leaves, and it's

mostly present there in the inorganic form.  The water the hijiki grows

in is not necessarily contaminated; it's more a case of a plant that

selectively absorbs more As thasn other plants.  These are called

bio-accumulators, and there are plants that accumulate nickel, zinc, selenium,

etc. 

Once it has been ingested, it will slowly be excreted

and the liver will move it to the skin, hair, etc, but if too much

arsenic is ingested in a short time, the liver will accumulate the excess,

but over time will continue to get rid of it.  Unless you had a massive

exposure, your body will get rid of it over time.

As to why no one has issued a warning, all I can tell you is that CFIA

is a young, quite assertive agency, and it tends to be more proactive

than most government agencies.  They're not always right, though, and

some people consider them to be too quick to react.  I don't personally

agree- they probably felt obliged by ethics to let people know about

this, but were cautious enough to not start a shitstorm by banning hijiki. 

As for other governments, I think the Japanese and US gov'ts have known

about this for some time ( the work done by people at Osaka Prefecture

Univ, Kyoto U, Chiba Institue of Chemistry etc was done in 2000-2001)

so they are either cautious, callous, or have other things on their

minds.

Bottom line- err on the side of caution and don't eat it until you know

more about it.

I just sent off another email asking about this mysterious 'arsenic sugar' mentioned in Hiroyuki's link. Have no idea what compound this refers to, but from what I've read on other Japanese sites I'm wondering if it's a laymen's term for arseno-betaine or arseno-cholide, the two relatively harmless types or organic arsenic. But that would mean that the Japanese sites are mistaking these compounds for more toxic inorganic arsenic- a huge disservice to readers!

Anyway, hijiki is off the menu for now, but I hope to get to the bottom of this.

[torakris]

This is very interesting about hijiki, I never had any idea.

But for anyone like me who would prefert o go out happy and eating the foods they like here are some recipes:

scrambled eggs (or omelet) with hijiki:

http://recipes.egullet.com/recipes/r1082.html

simmered hijiki with carrrots and aburage:

http://recipes.egullet.com/recipes/r1081.html

[smallworld]

About arsenic sugar:

The right technical term is probably arseno sugar (although I am not 100% sure).

Thank you Hiroyuki, I was able to find a wealth of information about arsenosugars, which I've never heard of before.

It seems that hijiki contains a few different arsenic compounds- inorganic arsenic and arsenosugars. There is no question that inorganic arsenic is highly toxic, but there are two things that no one seems to agree on:

First, does hijiki even contain inorganic arsenic? Most of the English-language sources confirm that it does, but I couldn't find any Japanese sites that even mentioned inorganic arsenic (this could be more to do with my poor reading skills though).

And second, about arsenosugars. Most sources, in English or Japanese, say arsenosugars abound in hijiki, but strangely the CFIA warning doesn't even mention them.

More to the point, are arsenosugars really harmless? Again, the English and Japanese sources differed here, with Japanese research apparently proving that arsenosugars pass through the body without causing any harm. English-language sources, however, mention research that shows that arsenosugars are metabolized in the body into a compound called dimethylarsinic acid (DMAA) as well as other forms of arsenic. Not much is known about DMAA, but it certainly can't be considered harmless.

This site, http://www.clinchem.org/cgi/eletters/44/3/539 , hs this to say:

There is little information on the toxicity of arsenosugars. Toxicological effects of the unidentified arsenic species due to metabolism of arsenosugars are not known. However, the increases in DMAA concentration due to arsenosugar metabolism should not be ignored. Although the acute toxicity of DMAA (LD50 = 700-2600 mg/kg) is much less than that of the inorganic arsenite (LD50 = 10-20 mg/kg), the genotoxic effects of these arsenic species are not well understood and may not follow the same order. Several studies suggest that DMAA may be more harmful than the inorganic arsenic species.

Why is there such a big difference between the Japanese research and the western research? Are the laws of physics different here in Japan? Do these scientists not read eachothers' findings?

In short, this claim of hijiki's arsenosugars being harmless smacks of sugar-coating. Sites like this http://www.iseko.com/kona/page/situmon.html , where hijiki products are on sale, assure us that hijiki's arsenic is safe.

A little too sweet for me, thanks.

[Hiroyuki]

Thank you, smallworld, for your very informative post. But even after all this discussion, I can't stop eating hijiki. Coincidentally, I made a hijiki dish for supper yesterday.

Here is a photo of it. I usually add aburage (aburage is short for aburaage), but I used satsumaage (kind of fish sausage) this time. I usually add uchimame (beaten soybeans?) too. I wonder uchimame are available in the United States and other countries.

[growpower]

I've recently run into two types of seaweed I have never seen before and was hoping you guys could give me some more information about them.

I had seaweed number one while staying at an osen in Himi, Toyama. It was served in a slightly citrus flavored broth with vegetables and seafood. The seaweed itself was olive green, and shaped like tiny branches. The part that really perked my interest was the fact that it was encased in a gelatin like substance. At first I thought the chef had actually dipped each piece of seaweed individually in gelatin, but my dinner table neighbor explained that it came naturally like that. Unfortuantely I forgot to ask her what it's name is.

Seaweed number two I saw in grocery stores. It was labelled ととろ (totoro if I am remembering correctly). It's a varigated light green (almost stripe like) sheet. Can anyone tell me more about how to prepare it and what kind of dishes it's used it? Google searches turned up to many references to the movie my neighbor totoro for me to go through.

-thanks

[Hiroyuki]

Are they mozuku and tororo konbu?

Mozuku:

http://www.okimozuku.com/

Tororo konbu:

http://www.rakuten.co.jp/isekanbutsu/480101/709299/

You can put tororo konbu in soup, wrap it around a rice ball, for example.

[growpower]

Okay, yeah it was tororo, not totoro. my bad. After reading the posts though, they've perked my interest. I am going out to buy some tonite.

I am not sure on the mozuku though, it was hard to tell from the pictures. I am going to try to go to a grocery store and ask if they have any.

Is it available at most supermarkets?

Edited July 6, 2004 by growpower (log)