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Jan 8, 2008 06:18 PM

Trai Au

I found these in the produce section of Fubonn and had to have them. Of course, I had no idea what they were or what to do with them, but I trust in the powers of the world wide internet to see me through. At only $1.48/lb they’re a bargain even if they just end up as part of my voodoo death necklace. The label identifies them as “Bull Head / Trai Au.”

Clearly a Vietnamese name but google wasn’t all that helpful. We see two results in English and several in Vietnamese. I can’t read the latter and none of them look like recipes anyway so I concentrated on the former. One blogger also found them at Fubonn and didn’t have many hard facts to offer. The other found them at a market in Vietnam. He claims that the market lady told him that they were Trai Au and explained that they were Lotus Roots. Obviously he misunderstood. I know a lotus root when I see it and these things aren’t the least bit root like. I think they are thorns because they resemble the ant infested thorn bushes we fought our way through while hiking on Isla Providencia.

Cheyenne and I have prowled the markets of Vietnam ourselves and don’t recall having seen anything like it. Either they were out of season or they aren’t too common. Of course, we could have missed them while we were distracted by the live scorpions or the imitation cockroach extract (I kid you not, it’s called Ca Cuong).

They turn out to be pretty hard to get open. Forget about doing it by hand because of those spiky ends. A hammer works well but it doesn’t seem possible to remove the meat in one piece. I hit them until they break open then pry the insides out with a knife.

They are bland and mostly tasteless but very slightly bitter with the texture of mature coconut meat. I still don’t know what to do with them. It doesn’t seem worth the effort to eat them as nuts and I can’t imagine cooking with them either.

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  1. Good to have you posting again! No idea what these things are, but I see them often at Ranch 99 and in SF Chinatown, so there's a Chinese tie-in too. I remember thinking they were some kind of Oaxacan black pottery the first time I caught a glimpse of them out of the corner of an eye!

    1. They are nuts. rworange posted on them a few years ago. Lots of good info on the post. or go to

      1. Bitter and crunch?? I grew up eating this, and if someone told me they were bitter and crunchy (which is what mature coconut says to me), I would at them oddly.

        Out of curiosity, how are you eating them? My mother always boiled them, and while they were never the easiest to get open, taking a hammer to them seems, well, overkill. The texture inside should be akin to a drier boiled peanut (but still bland).

        1 Reply
        1. re: Ali

          The old thread linked above allowed me to find a lot of extra info. Once I knew the more common names it's easy to find references to them. It seems strange that Fubonn uses the two most obscure names to describe them.

          Anyway, to answer your question we were eating them raw. Now that I know they are considered toxic when raw it's a good thing they didn't taste too good;) I haven't tried boiling them yet, but thats the next step.

        2. These are also known as water caltrops, and there are a number of postings under that topic.

          1. In China, many years ago when we were there, these were sold on the street like chestnuts. They were cooked and you'd get a little bag of them to eat just like that. I bought them because they are seriously amazing looking but I honestly can't remember how they tasted. For some reason, I keep one in my purse. For good or bad luck - I don't know which.