Cashews: the nut you can’t buy in a shell

Ever since we discovered them, we have been enjoying (and eating far too many of) the highly addictive Thai Lime & Chili Cashews from Trader Joe’s. These things should carry a warning label: “CAUTION: MAY BE HABIT FORMING.”

Anyway, while we eating them, we were asked if we knew why you can’t get cashews in the shell. We had no idea. Actually, we’d never thought about it. But, come to think of it, you can get almonds, walnuts, pistachios, brazil nuts, hazelnuts, peanuts, chestnuts, pine nuts, pecans, and even macadamia nuts in a shell, but not cashews.

Why? It turns out that the cashew shell is toxic. However, that raised the question of what a cashew looks like in its shell. Again, we had no idea. When we found out, we knew more people should see it. Weird looking, isn’t it? And caustic, too!

Cashews, like many of the culinary nuts listed above, are not true nuts in the botanical sense. True nuts develop a hard wall around the seed (e.g. hazelnuts). Cashews instead have a lining around the seed that is filled with a nasty fluid.

Cashews are in the same family (Anacardiaceae) as mangoes, pistachios, sumac, and poison-ivy. Many plants in this family produce Urushiol, an oil that can cause a nasty, painful rash. (Our friend Dan had not been told about this when he came across them in Thailand Brazil, and burned his mouth on a fresh cashew. Ouch. He has some pictures of the local “caju” fruit here.) The cashew stores this icky stuff in the lining around the seed, which makes cashews very difficult to process. They are usually roasted to release the fluid, which is collected for other uses, such as varnish. After that, the hardened lining must be removed by hand.

That’s pretty weird, but it gets weirder. In the cashew, the ovary develops outside of the fruit, which really makes it a false fruit, since by definition fruits have seeds inside. The false fruit attached to the false nut looks like a pear with a little boxing glove hanging off the bottom. When ripe, the whole thing falls off the tree, and the bottom part is gathered for processing. The false fruit (called cashew fruit or cashew apple) is edible, but it is very perishable. It is often left to rot, but can be eaten raw, cooked, or used to make a liquor called feni. While the fruit and its juice are available in parts of the world where cashews grow, they are apparently too perishable to appear in stores in the US.

Thai Lime & Chili Cashews

There is a lot more cool information about cashews out there. This article has plenty of additional details including uses, folk medicine, cultivation, and biotic factors, among other exciting topics. We recommend eating Thai Lime & Chili Cashews while furthering your knowledge.

23 thoughts on “Cashews: the nut you can’t buy in a shell

  1. > When ripe, the whole thing falls off the tree, and the bottom part is gathered for processing. The false fruit (called cashew fruit or cashew apple) is edible, but it is very perishable. It is often left to rot, but can be eaten raw, cooked, or used to make a liquor called feni. While the fruit and its juice are available in parts of the world where cashews grow, they are apparently too perishable to appear in stores in the US.

    It’s very easy to buy cashew/caju juice in Brazil, either ready-to-drink or to be mixed with water (unfortunately it does not mix well, one must stir often).

    It’s _very_ good with ice, it’s not citric at all, but rather has a starch-like feeling. Usually very sweet, too — it’s one of my wife favourites.

    The pulp can also be bought frozen, so availability is not a problem. Therefore, I find it difficult to believe it is "left to rot" these days…

    There’s a lot of recipes with it, too… candies, main dishes etc. Search "receita caju".

    And drinks, like this from :
    (also see )

    Caju amigo (Friendly cashew):

    1 cup of tea of cashew juice
    1 cup of tea of gin
    juice from 1 lemmon
    sugar to taste
    ice rocks

    How to:
    Mix all in a blender and serve cold. Drink immediately or keep in refrigerator, adding the lemmon only at the time of drinking.

    Personal note: these fruit beverages can be quite tasty and alcohol is dangerous. You know how much can kill you.

  2. My name is Ken and I’m addicted to Thai Lime & Chili Cashews from Trader Joe’s.
    It’s good to meet others with the same disease as I’ve always assumed that I was alone.
    It’s ruined me both physically and financially — I lost the house and my wife has now left with both our kids — and all because I can’t stop eating those damn Thai Lime & Chili Cashews from Trader Joe’s. I’m over 450 pounds and still can’t stop.
    My attorney says I have no case against TJ — not a leg to stand on (as if I could stand on one leg).
    Oh sh*t — just noticed that I’m getting low — good thing that where I live, TJs is open on Sundays, too.
    Pray for me, and support our new organization — Thai Lime & Chili Cashews Anonymous!
    Thanks for being there!

  3. You really shouldn’t hijack other people’s images. Copy them and put them on your own servers, using up other people’s bandwidths (or photos at all) especially without attribution is just wrong. Plus if you attribute a source, you come out looking better if the info in inaccurate. And eventually some one will goatse your ass, and as a reader, I certainly don’t want that.

    1. Whoops- our bad! I hadn’t realized that we weren’t hosting the image ourselves. We are now; thanks for pointing that out. We’ve usually been on the receiving end of this problem, and it bugs us as well.

      That said, pease note that the image, by Laura Lartigue, is in the public domain. Even though no attribution is required, we have provided what we think is the best kind of attribution available: a link to the description page for the photo on Wikipedia– (just updated to the Wikimedia page). If there had been a more authoritative and stable souce to link to, we certainly would have pointed our link there instead.

      Prompted by your comment, we just performed a little search and found that a (cropped) version of the image appears in this story, also by Laura Lartigue.

      Windell H. Oskay

  4. Hi, my name is Jay. When I was a Peace Corps volunteer in Honduras, I had a cashew tree in my backyard. I wouldn’t go out of your way to find some cashew juice. The fruit is very bitter and tastes pretty bad….I guess it’s an aquired taste. The kids seemed to like it and would ask me if they could climb my tree to get the fruit, which I would gladly allow on the condition that they give me the seed. The seed is easily roasted, like a chestnut.

  5. Reader Terri suggests reading "Germs, Guns, and Steel" by Jared Diamond for an in-depth look at food domestication, including cashews.

  6. When I was a kid, we had a cashew tree. In season, we get to eat the fruit. The nuts, in return, are pit-roasted (with shell) and once done, we crack the shell open and there you have the precious, edible cashew nut.

    Local folks in the Philippines believe that the smell of burning cashew nuts have an effect on chicken. I remember when my uncle used to chase us (he has lots of roosters and fighting cocks) when he sees us cooking cashew nuts. :) The smell is so aromatic and leaves a mile long trail – you simply can’t miss it.

    Man, I miss those days… :)

  7. Cashews don’t have a shell, they have a fleshy fruit.

    You can’t get them in the fruit because it burns your fingers.

  8. Nice article!

    I once lived in Chad and had a cashew tree in my yard. Since I love cashews, I decided to process them myself. Mistake. Even though I’d done the research and was careful I got a bad case of "poison ivy" from the smoke when I was roasting them. I did get a couple pounds of cashews, but it really warn’t worth the pain and suffering.

    The fruit on the other hand is a different story. They are scrumptious and with the seed on the outside they have no core or pit to eat around. I really don’t know why no one has commercialized them.

  9. My mother told me a story (From Sri Lanka) about why the Cashew fruit has its seed on the outside.

    Apparently, as God was creating the world he was approached by the Devil, who was upset that he had not been allowed to make something. So, in an act of kindness, God asked the Devil to make a fruit.

    The Devil went to work and formed what we now know as the Cashew fruit. He took it to God and said, "See? I can make something just as good as your creations."

    On looking it over, God asked, "But where is the seed?"

    The Devil, realising his mistake, just muttered, "Oh, I’ll stick it here." And with that, placed the seed on the bottom of the fruit.

    And there you have it.

  10. I live in Japan, and there are a lot of factory workers from Brazil in the area. The pharmacy next to my house has a selection of things from Brazil to serve the community, and what did I notice today? Cashew juice. I intend to buy a pack tomorrow and try it out.

    1. UPDATE: I purchased the juice and tried it out. I was unfortunately a bit disappointed. It’s something like a taste between an apricot and a loquat (琵琶: biwa) or along those lines. Sort of a generic yellow peach-esque flesh fruit. While the juice was disappointing, it seems like a fruit that would be infinitely better whole than juiced (like peaches or apricots or loquats). I’d like to try one some day if I get the chance.

        1. Do the cashew grows on a bush,or a tree ? I can not tell by this picture. I am teaching my 3 yr old about things that grows on trees and bushes nuts, fruit and vegetables can you help me on this question ? Thanks Melinda

  11. It grows on trees… I come from Panama (Central America) and we would roast the seed and crack them open and voila there was the cashew. Delicious! Nothing like a freshly roasted cashew.
    We would eat the fruit too… but I preferred it when mom made "chicha de marañon". Marañon is the name of the fruit (cashew apple). Chicha is when you add water to the fruit juice,you add sugar and lots of ice to make a cool refreshing drink. We also would make popsicles out of marañon.

    1. Hey upon tryingto answeer the question for my children I found this site and I would be greatly happy if someone could freeze the juice or fruit, and pack it with dry ice in a starafoam and send it down here to Texas we love fruit in the desert and sounds like a great tasting snack. Not to mention the expierience of tasting something alot of people know nothing about, Man you all sound really Lucky..

  12. I also am a peace corps volunteer but in west africa. From my experience the west african cashew apples are very tasty and sweet. Many are used for wines and jams. They are packed with vitiman C and can be a very refressing fruit on a hot day.

    You mentioned that you would roast the seed that was picked from the tree in your backyard. I find it hard to believe that you were able to roast a seed that was picked because when the fruits are picked from the tree the seed is not yet mature. An immature raw nut does not produce a edible nut. None the less Cashews are great and trader joe’s is annoying.

  13. You can’t eat the cashew fruit
    The cashew fruit is great for eating
    The fruit is sour and terrible
    The fruit is sweet and delicious.

    Isn’t the Internets great?!

    1. Also, we use the shells to make brake pads – pretty much every brake padd in the world contains cashew shells.

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