Wednesday, September 24, 2008

Making Acorn Flour

You can read lots of advice about making acorn flour by searching online. Kelly and Erik from Homegrown Evolution have an excellent section on it in their book, The Urban Homestead, which, if you haven't bought already you should right now. I made a few batches this time last year, before the book came out and what worked best is pretty much exactly what they describe. I wish I had the book then.

1. Collect your acorns.
Avoid anything that has a damaged shell, especially a dark hole or small circular scar on it about the diameter of a pencil lead. Those acorns have worms in them and are no good.

2. Shell the acorns.
This was the most time consuming part for me. I learned a trick for shelling acorns toward the end of last year's season: When dry, many will open themselves. I'm not sure if this is true of other types of acorns but our Live Oaks pop right open when dried out. If you wait for them to dry out, make sure that they get plenty of air, you don't want them to rot. If you have a dehydrator, you may consider speeding the process. Keeping them in the oven may work too if it has a pilot light.
3. Make acorn mush.
Put them up in a blender with some water. Don't be stingy with the water, you'll be rinsing them out several times before your flour is ready. Think acorn smoothie.

4. Rinse out the tannins.
Acorns contain tannic acid which is bitter, and not good for your kidneys (or iron absorption) . The good news is that it is water soluble and easy to remove. Drape a cotton dishcloth over a deep bowl, pour in your mush and rinse the it with warm water. Wring out the mush by bringing the corners of the towel together and twisting. Taste the mush, if bitter, repeat. I have heard that you don't need to make mush before rinsing the tannins out. I tried this method and my acorns were still bitter after several weeks of changing the water every day. I also tried using boiling water to rinse the mush but warm water from the tap seemed to be the best balance between water usage, gas usage and time - at least for me.

The waste water is good for plants.

5. Dry out the mush.
Next spread the mush out on a cookie sheet and either leave it in the sun on a hot dry day, put it in your dehydrator, or put it in your oven after you baking some cookies or something and let the residual heat do the job. Stir the mush occasionally to speed the process. If it clumps up and looks like ground beef it is probably going well.


Once the flour is dried out it may be a little coarse. You can put it in a cleaned out coffee grinder to get a finer texture. A good food processor also works and I am pretty sure they make attachable gadgets for mixers that really mill the flour if you get completely obsessed.

Our favorite use is acorn pancakes. Just mix the acorn flour 1/2 and 1/2 with wheat or other flour from your favorite recipe. I love the acorn flavor - slightly nutty, very hearty. If you make your own, let us know how it went.

45 comments:

  1. Thanks for the plug! Funny, we thought acorn processing got cut from our book. Glad to hear that it's in there since, despite the effort, acorn flour is pretty tasty.

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  2. Wow...that seems like a lot of work for some pancakes...

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  3. Thanks for the post! We have far more acorns than our squirrels can keep up with, but I'd been discouraged from using them because of the tannin issue. One more "accidental harvest" we can take from our small city yard.

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  4. Wow, this brought back memories. When I was in 8th grade, we went to a wilderness program and this awesome hippie Snowbear taught us how to make acorn pancakes. We would gather and shell and do much of the work, but then we would make pancakes from the previous group's flour. I definitely think this is a perfect group activity ... where you do the shelling together while chatting (like crawfish in Louisiana or momo in Nepal). I love social food prep. Thanks for reminding me how great these are. You rock.

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  5. Tried this once many years ago--boyfriend took care of the gathering/leaching/grinding stuff (he leached first, don't remember how many soakings it took but quite a few), and I did the baking. The flour was a bit coarse but fairly uniform, so I used it to make a crust for a ginger cheesecake. It turned out wonderfully! The tea-like flavor of the acorns was a great complement to the creamy tangy filling.

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  6. A ready device for leaching chopped acorns is the tank to your standard flush toilet.
    Contrive to hang the bag of chopped acorns in the tank,
    unused freshwater don't fret, and every flush is a leach down the tubes.......

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  7. I'm curious if you've tried the "waste" acorn water as a nut milk- your process is identical to making almond milk/ flour.

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  8. Euell Gibbons covered acorns in the first chapter of his Stalking the Wild Asparagus. He noted that acorns from white oaks needed very little processing and had similar recipes to yours.

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  9. @ d

    The reason for 'milking' the flour is to remove unhealthily high tannins, so I think that drinking the 'milk' would be a bad idea.

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  10. Thanks for the recipe and the step-by-step. Really not a lot of extra work for pancakes, if you figure in growing, harvesting, threshing, and milling the wheat. We've made acorn mush before, and it's really good -- kind of reminds me of avocado flavor. It's amazing to me that, here is this food that was the center of Californians' diet for millenia, and now we just sweep the acorns up and compost them, or feed them to hogs.

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  11. Thank you for sharing! I found Sawtooth Oak acorns recently. I boiled the few handfuls of shelled and not fully husked nuts about 8 times over. The brown color of the water only diminished, not disappearing. I let them dry over night and roasted them to being almost total brittle and dark. The flavor was not bitter, but a starchy astringent, sometimes a little sweet. I ground them into flour, mixed with wheat flour and baked them into a persimmon-ginger scone batch.

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  12. These acorns look different (longer, thinner) to the acorns I'm used to. Are they a particular type?

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  13. Acorns were a staple of Native Americans in California. The grinding came first and then the flour was taken to running water, laid out and water poured over them repeatedly until the tannic acid was washed out. The resulting meal was then cooked in baskets with water, meat, fish, seeds, herbs, etc. The cooking was done with cooking stones - heated rocks that were dropped in the basket, stirred and then replaced with another until the acorn soup was done, thus leaving the basket intact to use indefinitely.

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  14. Thanks Everyone for the great comments. If you decide to make your own flour, we'd love to hear how it goes. To answer questions by d and and dan c:

    To d: I think greenglyph is right about the milk - it would not only taste extremely bitter but it would probably not be very good for you. I pour ours on the compost pile.

    To dan c's question about the type of oak, this is is a coastal live oak. The acorns are longer and more cylindrical than most. They also contain more tannins than most. kindlyrat's brings up Euell Gibbons statement about white oak acorns needing very little leaching.

    I would love to try other types of acorns. In fact there is a park in Ojai, CA that we visited last fall which had the largest acorns I have ever seen. Many of them were larger than a Brazil nut and they were extremely plentiful - heaps of them everywhere.

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  15. i've always wanted to try this ever since I read "My side of the mountain" about a million times when I was young. The main character - Sam Gribley - who ran away to live off the land in the Catskill Mountains, practially lived on them!

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  16. Acorns were the ticket to survival for some of the settlers at Jamestown. Connie Lapallo's book, Dark Enough to see the Stars in a Jamestown Sky details the lives of some of the women of Jamestown, and how they survived the Starving Time by stockpiling acorns. http://www.connielapallo.com/AcornFlour.htm

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  17. I had to chuckle a little at this. I tried this when I was a kid and it tasted horrible! But in reading your tut, I'm sure I didn't rinse all the tannins out properly.

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  18. This sounds amazing! I'm in Florida, and our oaks are just starting to drop the bezillions of acorns we'll get this fall, and I knew you could make flour but I didn't know how. Thanks!

    Ours are also called live oaks, but the acorns are mostly small and round. Brittle enough that I break them when I bike over them, so maybe they won't be too hard to shell...

    I'll keep you posted!
    ~:)

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  19. Thanks for the heads up on acorns being edible if properly handled. There are tons of Live Oaks and their acorns around my part of Texas. About how many nuts does one need to make a cup of flour?

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  20. Woolysheep,

    That's a good question - I'd say about 2 cups of shelled acorns would make a little over a cup of flour. It is a lot of work to make for small batches like that though so I'd recommend making more and storing it in the fridge - approximately the same amount of work but more four and it keeps a long time, just like other flours.

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  21. re-reading my last comment I can barely make sense of it. That's what happens when you are trying to type with a 4 year old climbing your back like a tiger with it's tail on fire.

    What I was trying to say is it's the practically the same amount of work to make a little or a lot, so you might as well make a lot. The ratio of fresh shelled acorns to dried flour is approximately 2 to 1. Hope that helps - makes more sense to me anyway.

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  22. I am looking to dry acorns that I use for a school program at the State Park I work at. We need something quick, effective and easy for those doing the drying, hence I am thinking of buying a dehydrator. My question is: at what setting and for how long should I dry acorns to ensure dryness and destruction of any leftover grubs?

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  23. Lisa,

    I think that you could dry yours out by putting them in the oven on low for a little while. I wouldn't buy a dehydrator just for this project.

    If you are shelling the acorns you are going to see which have worms and which don't as you open them so I am assuming that you are not shelling yours. If that is true, drying them out may open the shells. As you can see in the 3rd picture, ours pop open when completely dry.

    I hope this helps, good luck with your project.

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  24. Wow - terrific tutorial. Thanks - look forward to checking out your blog in depth!

    Cheers,

    Mungo

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  25. I met a Greek octogenarian couple(15 years ago) while on holiday in Kefalonia who told me of the many use's of acorns during the Nazi/Mussolini occupation. Among them was flour , boot black and a rough (flavour wise) coffee type beverage. I have always wanted to experiment but been a little shy of trying, I will now(fingers crossed). Rob .

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  26. I collected several thousand acorns from my yard--a big basketful. I made the mistake of putting the basket aside and not sorting them right away.

    I went away for work for a few days, and when I came back, there were many MANY little larvae worms on my floor, more were around the acorn basket. Yuck!

    I had to dump the acorns back into the yard for the squirrels. Next year I'll only pick up good ones and sort them right away!

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  27. Wow! I had no idea you could do this with acorns. Now I wish we actually had some around here.

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  28. My Husband and I live in an apartment community with lots of oak trees...I came upon your post in the CRAFT Magazine blog and decided to take advantage of the abundance of acorns and was pleasantly suprised by the results. I made some muffins found here http://cindyha.wordpress.com/2008/09/29/nuts-about-acorns/ They were so yummy :)Thank you for sharing!

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  29. Hello,

    I'm Nana from Indonesia

    Is it possible to plant oak tree in tropical country like Indonesia?
    Is acorn flour easy to find? because I need to make the acorn jelly.
    Thank you

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  30. Hello Nana,

    I am not sure about planting oaks in a tropical country. They grow in the Southern United States where it is hot an humid but I haven't heard of them growing in the tropics. Oaks are notoriously slow growing trees so the time until a planted tree produced acorns could be very long.

    Dotorimuk is a Korean acorn jelly (maybe the style that you are making?) which leads me to believe that you might be able to buy the flour from a Korean market either online or in your area if one exists.

    I wish I could be more help.

    good luck!

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  31. Unfortunately there are no Acorn bearing oaks that grow in tropical locations. Below the equator in sub-tropical regions I have heard that a few Oak species flourish but I don't think they drop edible Acorns.

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  32. Good pass time, keep you active and away from the TV. You can also buy acorn starch at asian stores that carry Korean food. Reconstitute it into a tofu like block. Slice and serve with soy sauce, sesame oil, ground sesame seeds and chopped green onions. This is a summer dish, usually lunch or a snack and is served cold or room temperature. Never warm.
    For reference only. Find a store it is much cheaper than online.

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  33. An effective way to separate grub-infested acorns from good ones before shelling is to dump your harvest into a bucket of water. Bad ones float, useable ones sink.

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  34. my valley oak acorns get me about 2 cups of flour for 2 pounds of unshelled acorns. i make chocolate and acorn flour drinks all the time.
    good for ya!

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  35. Thanks for this info. I just collected a bag of acorns from trees in the streets of Canberra, Australia. Here it is not so tropical so they grow here (I'd never seen them before since i used to live alot more north). They are now shelled and everything. I'm not sure yet though if to leach them before or after grinding. They are a type of red oak acorn so will have lots of tannins. I may try half of them one way and half of them boiling on the stove first.

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  36. Hi anonymous,

    So great to hear about fall harvesting as our spring is just taking off.

    I think you should proceed with your experiment as we did but we found that putting the acorns in the blender fort made the leaching much faster.

    Good luck and let us know how it goes.

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  38. We bought property in Pegram, TN last year and we have acorns all over the back and sides of the property along with those famous "wild hickory nuts". Yesterday we were discussing how to use the myriad of acorns- now we know.

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  39. Great tutorial, thanks- I live in Portland, Oregon and have discovered a number of Oak trees right by the building I work in downtown. They have dropped oodles of acorns, which I spent about an hour scavanging for yesterday. I've had great success so far with not getting wormy ones that I found on the ground, so I suspect they are very freshley fallen.
    I was wondering if you happen to know a good rule of thumb for identifying acor & oak varieties. I actually have no idea what type these are, as they bear superfucial reseblence to a couple different kinds of oak. Do you happen to know a place where I could find what types live in my area so I could narrow it down? Most descritions just say "sampy lowlands" or "dry fertile soil" or whatnot- pretty vague.
    thanks!

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  40. Hi Anonymous,

    There are a few oak species that grow in Oregon. If the trees are native they may be the lovely Oregon White Oak (http://oregonstate.edu/dept/ldplants/quga10.htm) If it's not that one it must either be a Canyon Live Oak (http://oregonstate.edu/dept/ldplants/quch9.htm) or the California Black Oak (http://oregonstate.edu/dept/ldplants/quke12.htm)

    The black oak and the white oak look pretty similar but the black oak has spikier leaves and the caps cover half the acorn as opposed to the white oaks which have more rounded leaves and the caps only cover 1/3 of the nut.

    Here is a list of native (and naturalized) Oregon trees listed by height. Oaks are in the 50-75 foot section.

    Good luck with processing your acorns!

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  41. I live in Pedro, by the harbor, and there aren't a lot of oaks here on the peninsula... my dad suggested driving out to the valley (where there are lots of valley oaks) but i'm still not sure where to go. (i have a 3 year old and a baby, so there's not a lot of room/patience for nice walks without acorns)... where have you collected yours from? do you know specific spots where we could gather?

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  42. For those who have a hard time finding oak trees to gather acorns from, try planting a few oak trees as a future investment to guarantee yourself acorns in the future.

    Thank you for providing this information for others to use. :D

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  43. Apparently acorn meal is used to fatten deer, and hunters buy acorn meal to do this. It's sold in 5-lb. bags for between 13-16 bucks. (Pun not intended.) The product I googled is called Vita-Rack. Does anyone know if this could simply be leached and then processed for human consumption?

    @Anonymous, I live in Portland too. So many oaks grow here. The ones that have really rough bark and more contorted limbs are Oregon White Oak, Quercus garreyana, but lots of east coast Red Oak and similar deciduous oaks are here too.

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  44. I obtained some ground acorn meal from a demo at San Antonio Mission. I leached the meal with lots of hot water, then simmered in in a pot on the stove with some water to make acorn mush. It tastes like a combination of crayons and wood. Not like something I'd want in pancakes or scones. Did I do something wrong??

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  45. Anonymous, you may need to leech it some more. It took a really long time for us to get the tannins out of the flour. We pour boiling hot water on it over and over until the meal tasted nutty. Keep pouring the hot water over it. Also, was the acorn meal fresh? If it was ground a long time ago & not stored properly, it can go rancid. Talk about nasty taste. Rancid will do it every time.

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