World’s Largest Acorn

 Acorn: More than a survival food

The first time you eat an acorn it makes you wonder what the squirrels are going nuts about.  As the bitterness twists your mouth into a pucker it reminds you animals can eat a lot of things we can’t… unless we modify them.

A lot has been said about acorns. I’ll try to say a few things that haven’t been said. Let’s start with that fact that the world’s biggest acorn is in Moore Square Park in downtown Raleigh, North Carolina. Raleigh calls itself “The City of Oaks.” The “Big Acorn” is ten feet tall and weights 1,250 pounds. I’d hate to meet the squirrel that can carry it away. But, it does remind me of a general rule of thumb about acorns: The bigger the cap on the acorn, the more bitter it will be.

The English word “oak” is some 1,260 years old. In German it was “eih” ending up “eiche” The Dutch extended it to “eychen” or ” eychenboom.” (I went to school with a “Cossaboom” meaning cherry tree.) Oaks are also mentioned in ancient texts.  Greeks of old said “dryas.” Modern Greek say “dris.” It was the preferred tree of Zeus. Those faithful to Zeus gathered around oak trees. The Celts preferred to knock on oak wood. One variation of their word for oak was “dair, the fourth letter of the Celtic alphabet and part of the name of the city Kildare (means “Church in the Oaks.”) Often associated with strength, the US military awards gold “oak leaf clusters” for exceptional bravery. Oaks have been a significant part of every culture around them.

The larger the cap the more tannic acid

The word “acorn” is a combination of “ak” for oak and “corn” meaning seed thus acorn means oak seed. The Greeks say velanidi, the Spanish bellota, the French gland, Italians glanda, Portuguese, glande, and in the forgotten fifth romantic language, ghinda in Romanian. Those Romans got around. All the Romantics come from the Latin word for gland, which also lent itself to the medical term for a certain acorn-like part of the male anatomy.  The acorn is also one of the few nuts or fruits that is not directly named in Modern English after the tree it comes from which is why one does not hear of oak nuts… walnuts, beechnuts, hickory nuts, oak nuts… gland… it could all get rather naughty.

The smaller the cap, the less tannic acid

At least 450 species of oak populate world wide. Some 30 species in the United States have been used for food and oil. The Live Oak is the most prized, not only for food but particularly ship building. Its very long, graceful limbs were ready-made for boat keels and ribs. In fact, the U.S. Navy once had its own live oak forest just for boat building. Sold off long ago, the Navy began stockpiling Live Oak in 1992 for restoration of the USS Constitution. It got 50 live oaks from Florida in 2002 of 160 that were cleared for a golf course near Tallahassee. Just as 200 years ago, the trees were selected for their natural curves for the ship. In the white oak family, the Live Oak’s acorns are among the mildest one can collect. Botanically the Live Oak is Quercus virginiana. Quercus (KWERK-kus ) was the Roman name for the tree and virginiana (ver-jin-ee-AY-nuh) means North America and usually where the species was first noticed, such as Virginia.

Storing acorns the Acorn Woodpecker way

The seed crop from an oak, the acorns, is called a “mast” which means “food” and putting on a crop of acorns is masting. It is tempting to say it is probably related to the word to “masticate” meaning to chew but it isn’t. Mast came from the Middle English word “mete” meaning meat, which at that time meant any food, and we still use it abstractly in that way, as in “Education became his meat and experience his drink.”  Mete came from the Italian word madere which came from the Greek word, madaros, meaning to be wet. That takes a bit of explaining. Ancient Greeks divided food into two large categories. “Wet” food was food fit for humans and pigs. Dry food was fit for cattle and fowl.  Now you know.

Acorns are quite nutritious. For example, the nutritional breakdown of acorns from the Q. alba, — the white oak — is 50.4% carbohydrates, 34.7% water, 4.7% fat, 4.4.% protein, 4.2% fiber, 1.6% ash. A pound of shelled acorns provide 1,265 calories, a 100 grams (3.5 ounces) has 500 calories and 30 grams of oil.  During World War II Japanese school children collected over one million tons of acorns to help feed the nation as rice and flour supplies dwindled.

Live Oak leaves have no teeth

Oaks fall into two large categories, those that fruit in one season, white oaks, and those that fruit after two seasons, the black oaks and the red oaks. The latter category is far more bitter than the former. The first category have leaves with round lobes and no prickles at the end of the leaves. The black and red oaks have prickles at the end of their leaves. They also  have scales on the cups of the acorns, hair inside the caps, and a sheath around the nut (which always throws a color even when the tannin is leached out.) Some times those in the first category don’t need any leaching, or very little. The rest always do. But first, separate the acorns.

Floaters are bad or have a usable grub in them

To separate acorns dump them into water and remove the ones that float.  Take the ones that sink and dry them in a frying pan on the stove or in the oven at 150F or less for 15 minutes, preheated. Or put them in the sun for a few days. You don’t want to cook them yet, just dry them off and shrink the nut inside making them a little easier to shell. The yield, not counting bad acorns, is 2:1. two gallons of usable acorns in the shell will yield a gallon of nutmeat. We must leach out the tannic acid it can damage our kidneys, Most unleached acorns are too bitter to eat without leaching.

Soaking in cold water, minimal energy and the starch is not cooked

There are three general ways to leach acorns. The least common way is to bury them whole in a river bank for a year, which turns them black and sweet, good for roasting. The other method is to grind them into a course meal and soak several days or weeks (depending on the species) in many changes of cold water until the water runs clear. These will be slightly bland but good for making acorn flour. (Sometimes the leached acorns will be dark but sweet afterwards.) The third way — boiling — is least preferred because if done wrong it will bind the tannins to the acorn and they will not lose their bitterness. Also, when you boil the acorns you also boil off the oil with the tannins, reducing  their nutrition. That oil, however, is very nutritious. At this writing it is selling for $182 a gallon. You can make it for far less. There is actually a fourth method that requires lye but it is not commonly used nor have I tired it.

Boiling speeds up the process but cooks the starch

The boiling process requires two pots of boiling water. Put the acorns in one pot of already boiling water until the water darkens. Pour off the water and put the hot acorns in the other pot of boiling water while you reheat the first pot with fresh water to boiling. You keep putting the acorns in new boiling water until the water runs clear. Putting boiled acorns into cold water will bind the tannins to the acorn and they will stay bitter. So always move them from one boiling bath to another. Putting acorns in cold water and bringing the water to a boil will also bind the tannin. So it is either use all cold water and a long soaking or all boiling water and just a few hours of cooking. There is one other difference between the two methods.

Mrs. Freddie, a Hupa, pours water over ground acorns in a sand basin

The temperature at which you process the acorns at any point is critical. Boiling water or roasting over 165º F precooks the starch in the acorn. Cold processing and low temperatures under 150 F does not cook the starch.  Cold-water leached acorn meal thickens when cooked, hot-water leached acorn meal does not thicken or act as a binder (like eggs or gluten) when cooked.  Your final use of the acorns should factor in how you will process them. If you are going to leach and roast whole for snacking then boiling is fine. If you are going to use the acorn for flour it should be cold processed, or you will have to add a binder.

The finer acorns are ground the quicker they leach

Personally, I grind mine in a lot of water to a fine meal, let it set, then strain. I add more water to the meal, let set and strain. I do that until the water is clear or the meal not bitter. That takes a few days to a week. Then I dry it in the sun, unless there are squirrels about, then in a slow oven (under 150º F.)  I end up with a meal or flour, depending on the grind, that will not crumble when cooked.

There are nearly as many ways to leach acorns as there are opinions about acorns. Another way is to put the shelled acorns in water in a blender or food processor and blend them into a milk-like slurry. Put that slurry in a fine mesh bag and then massage that under running water like a faucet. It works very quickly but of course some meal and oil is lost in the process. But it turns hours of leaching into minutes. Of course, leaching them in an unpolluted stream is the easiest way but you can also arrange for a container to leak slowly. Simply put a cloth on the bottom to hold the meal in and fill the container when it is empty, or run the faucet slowly to maintain the leaching. Another ways is to clean out the tank on your toilet and put the shelled acorns in a mesh bag in there. Every flush will remove tannic water and bring in fresh.

Acorn bread in a classic cast iron pan

Many Native Americans preferred bitter acorns to sweet ones because they stored better. If after leaching there is just a hint of bitterness that can sometimes be removed by soaking the acorns in milk for a while.  The protein in the milk will bind with the tannin in the acorns and can be poured off, if there is just a little. To get oil from the cold-leached acorns, boil them. The oil will rise to the top of the water. Also, charred acorns can be used as a substitute for coffee but really nothing is a substitute for coffee.

Acorn Grub

Whole leached acorns can be roasted for an hour at 350º F, coarsely ground leached acorns slightly less time.  They can then be eaten or ground into non-binding flour. To make a flour out of your whole or coarsely ground acorns, toss them in a blender or food processor. Strain the results through a strainer to take out the larger pieces then reduce them as well.  Acorn flour has no gluten so it is usually mixed 50/50 with wheat flour.  Since acorn flour is high in oil it needs to be stored carefully and not allowed to go rancid. Remember cold processed acorn flour has more binding capacity than heat processed acorn flour.

Live Oak acorns top the food list for birds such as wood ducks, wild turkeys, quail and jays. Squirrels, raccoons and whitetail deer also like them, sometimes to the point of being 25% of their fall diet. Interestingly, the tannin tends to be in the bottom half of the acorn which is why you will often see a squirrel eat only the upper half of the acorn. Squirrels are also not fools. They will eat all of a white acorn when they find one because it is the least bitter. They will bury the very bitter red and black acorns so over time some of the bitterness is leached into the soil. Raiding a squirrel’s hoard will get bitter acorns.  By the way, acorns shells and unleached nutmeat have gallotannins which are toxic to cattle, sheep, goats, horses and dogs.

If you use the boiling method don’t throw away the tannic water. The water has a variety of uses. With a mordant it can be used to dye clothing. The tannic acid also makes a good laundry detergent. Two cups to each load but it will color whites temporarily a slightly tan color. Tannic water is antiviral and antiseptic. It can be used as a wash for skin rashes, skin irritations, burns, cuts, abrasions and poison ivy. While you can pour the tannic water over poison ivy, if you have the luxury freeze the brown water in ice cube trays and use the cubes on the ivy eruption. If you have a sore throat you can even gargled with tannic water or use it as a mild tea for diarrhea and dysentery. Externally dark tannic water can be used on hemorrhoids. Hides soaked in tannic water make better leather clothing. Using the brown water turned hides tan colored and that is why it is called tanning and from there we get the words tannins and tannic. In traditional tanning methods, whole hides are soaked in a vat of tannin water for a full year before being processed.

Oak trees begin to produce acorns at about 20 years years old but usually the first full crop won’t happen until the tree is about 50.  The average 100-year old oak produces about 2,200 acorns per season.  Only one in 10,000 will become a tree.

Besides dyes paints have also been made from the oaks. It also a dense wood for working and weights 75 pounds per dry cubic foot. The hull of the US warship, USS Constitution, was made entirely of oak, white oak covering over a live oak core. At the waterline she was 25 inches thick. Eighteen-pound cannonballs bounced off the oak, notable in the 1812 battle with the HMS Guerriere. That battle and the subsequent loss of British ships caused the British to issue the order that no ship was to attack the Constitution singlehandedly. The Constitution, as of this writing, is still on duty and berthed in Boston.

Peter Becker’s “Newtella”

Sprouted acorns are also edible as long as they haven’t turned green. I’ve heard from German forager Peter Becker has a slightly different view of what to do with acorns.

“What I do to prep acorns for consumption is let them germinate, so the starches turn into malt sugar. I’ve only just developed a new product with acorns to introduce this precious nut to public because acorns are generally considered inedible here in Germany. NewTella is a sweet bread spread just like Nutella, the famous hazelnut creme, except that all ingredients are locally available, it has less sugar and the only fats are from the acorn. The basic preparation is to roast leached, peeled and germinated acorns, boil 1 part acorns with 3 parts of apple juice, when soft process them smoothly, add 20 % sugar with pectin. This bread spread is also a great way to preserve acorns and can be used for cookies. It’s a great way to promote this gigantic untapped resource and jazz up general nutrition.

A few exchanges about Peter’s process is below in the comments. He shells them, leaches them (cold water) and sprouts them before using them to make his NewTella. That helps convert the starch to malt, which is sweet. To visit Peter’s site click here.

Lastly you may have a use for those acorns that float. Most of them have a weevil grub in them, the Acorn Curculio. Look for a little 1/8 inch hole. In time that grub will crawl out and burrow into the ground for a couple of years turning into a full-fledged insect. You can use that grub in the acorn as bait for fish. Or, you can let it crawl in to a bucket of dirt or sawdust or a container of oatmeal where it will make a cocoon which you can then open later and use for bait. Store live in the frig. Also, squirrels like the grubs so it is not beyond reason to use them for bait for squirrels. And to answer your question, the grubs are edible by humans raw or cooked.


Acorn Bread

2 cups acorn flour

2 cups cattail or white flour

3 teaspoons baking powder

1/3 cup maple syrup or sugar

1 egg

1/2 cup milk

3 tablespoons olive

Bake in pan for 30 minutes or until done at 400 degrees.

A far more simple form of acorn bread is to make a thick acorn porridge out of cold processed acorn flour. Take a large tablespoon of the porridge and drop it into cold water. This causes the porridge to contract. Take the lump out of the water and dry.

Green Deane’s “Itemized” Plant Profile

Autum Acorns

IDENTIFICATION: Acorns, small nut with cap. Rough and larger caps belong to the more bitter acorns.

TIME OF YEAR:  Usually late summer, fall, tree do not produce every year.

ENVIRONMENT: Oaks inhabit all kinds of environments.

METHOD OF PREPARATION:  Numerous once leached of tannins.: out of hand, flour, candy.


The tannins have been used as an astringent as well as antiviral, antiseptic and antitumor but could also be carcinogenic. The mold that develops on acorns has antibiotic properties.

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{ 187 comments… read them below or add one }

Paul October 5, 2015 at 12:19

Well-written article with historical and practical info. I’m partial to grinding, then leaching in scalding (not boiling) water, as seen in my video:

Toasted meal in yogurt is good.


Anthony Pennington July 16, 2015 at 01:56

There are so many nut milk options in stores now. Any tips of making acorn milk? I wonder how it would taste.


Kathleen Becker July 8, 2015 at 20:07

Another article full of fabulous info, thanks, just a quick add-on from an expat forager in Lisbon: the Portuguese seem to say “bolota” (I’ve just come across an article in a national travel mag about the renaissance of the bolota, as liqueur, flour, etc. The company is called Terrius).


K Prendergast June 13, 2015 at 12:47

Thanks for all this excellent info!! I have 11/2 acres of white oak about half produce 2-3 bushels yr… I’ve always saved them for winter, deer forage. I’ll try your process for people- winter forage… Thanks again!!


David Escobar June 7, 2015 at 04:38

You mention that the oil sells for $182 a gallon. I’ve been searching the web trying to buy some and find nothing. Does anyone know where to buy it?


Ina March 23, 2015 at 18:18

Hello. I just moved to Asheville, started planting in the yard, and noticed thousands of acorns out of their shells and sprouted everywhere. I have read every single comment on this and havent read anything about acorns that are naturally sprouting outside. They are beautiful. White with a thick sprout. I tasted it…no holes…no grubs…and its sweet. So what can i do with them at this point? Some have rooted in the ground which i am just pulling out. But ohers are just sprouting without roots all over the yard. Again, they are blemish free and taste sweet. My 4 year old wants to cook them up. Thoughts?


Vahid February 26, 2015 at 17:59

Many years ago, in my country (Iran) people used Oak for production bread. They removed tannin and finally made bread. Recently, researchers used Oak starchas substrate (carbon source) to produce Bio- Butanol and Xanthan gum . Iranian Acorn (Oak) has starch about 60%, tannin 10% and other components.


Laurie Heijn December 10, 2014 at 10:59

You have not mentioned that the reason acorns must be leached thoroughly before using is that there is so much tannin in them they can, and do, cause kidney failure in humans and some animals (ruminant animals especially). This should be made perfectly clear in your article, as there are plenty of people who might take shortcuts before eating them. Please do correct this very important missing fact in your article. By the way, the same is true of fiddlehead ferns; they should be boiled in several waters, throwing out all the water each time before consumption. And the reason rhubarb leaves are highly toxic and should never be eaten is because of the high content of tannic acid.


Old European Culture November 14, 2014 at 08:26

I have written couple of articles about oaks and acorns and their almost simbiotic link with people since paleolithic times. You might find them interesting.

Have you ever wandered why oak trees and oak groves were considered sacred in the past? Maybe the reason is that oaks are one of the most useful trees in the world.

You can read more here:

In my last post I talked about Oaks and how useful they were and are to people. The last thing that I said in my last post is that acorns had been eaten by humans since at least late Paleolithic times right up to modern times, and that I would write about acorns and acorn eaters in my next few posts. In this post I will write about archaeological evidence we have for human consumption of acorns during the Paleolithic, Mesolithic, Neolithic, Copper age, Bronze age and Iron age. I hope you find the data presented in this post as eye opening as I did find it, and that you will start seeing acorns in a completely different light from now on.

You can read more here:

In my post about oaks I talked about the oak tree and how useful this tree was and still is to people. In this post I would like to explain why I believe that people were as useful to the oak trees as the oak trees were useful to people. I believe that the influence that people had on the distribution of oaks in Europe could have been far greater then it is currently accepted. I think that the northward spreading of oaks from their glacial refugiums after the last ice age was actually the result of the northward spreading of humans from the same refugiums. I believe that it was humans who brought the oaks to the north of Europe. Let me explain why I believe that that was the case.

You can read more about this here:

I am continuing my oak acorn series with an article about primitive acorn cultivation and preparation…


Foraging the Ozarks November 11, 2014 at 03:11

I was gathering persimmons today and noticided hundreds of acorns in the stream. Some probably have been in the water for 2 weeks or longer. I’m guessing this will just aid in the leaching prosses. I know they will be from a variety of oaks, white, red, and black. I’m assuming different acorns can be leeched together. However since the tannin levels can differ and the red oaks red skin causes the water to stay red after tannin is gone it probably wouldn’t be advisable to leech together. Is there another way to test for the tannin? Maybe a pH tester that can check the acidity in the leeching water. On a pH chart 7 is nuetral anything under 7 is acidic anything over 7 is alkiline. A pH of 7 at 77°F (25°C) is considered pure water. Can this also be done to test tannin water? If yes, what is a tolerable pH level?


Green Deane November 12, 2014 at 20:31

Test by tasting. Try a little and wait several minutes. Sometime the bitterness takes a while to appear on the palate.


Laurel November 4, 2014 at 13:29

I see that the tannic water can be used on poison ivy. Is it good for other itches and bug bites as well? I’m trying to decide on toilet tank rinses or a method that saves the tannic water- and I am also covered in hives so it would be pretty convenient if the acorn water could help my mysterious itch.

Any other great uses of the acorn rise water?


Emily November 1, 2014 at 12:45

This is my first time attempting leaching of acorns. At first I tried cold leaching of the pieces. It was clear that was taking too long. So I ground them. Mine were not finely ground (I just used my food processor) and after two weeks plus of dumping off 2 to 3 times a day they were still very bitter. I was out of time for my project (for a class), so I decided to run under cold water for a couple hours. Still bitter. Then I decided to hot leach. Nine hours of hot processing later, they were finally not bitter. I got some seriously bitter acorns. I have no idea what the problem was, but I am very much discouraged from ever trying this again. If I ever do, I will be sure to grind them much more finely and try to remove as much of that inner skin as I can first.


Green Deane November 2, 2014 at 06:32

Which species can be quite important in that red and black oaks have much more tannin. Also red oaks have an inner red skin that colors the water red even after the tannins have been removed. Natives would bury red oak acorns in the river bank and leave them for a year or two.


Stephen October 24, 2014 at 13:11

I was hiking through the woods with a friend a few weeks ago and saw a massive amount of acorns on the ground and decided to find out if they were edible. I looked it up on google and found your site. I decided to experiment with a few of the acorns. Ive tried soaking one (shelled) in water for 5 days and it is still extremely bitter. The tree’s leaves have rounded lobs like the description of white oak but the nut is so bitter that it makes you salivate then completely dry up when you taste it. I noticed that if you chew it for a bit it begins to taste like molasses. Is there any special way to process this type or are these just unedible. Are they unsafe to eat if they are this bitter even after 5 days of soaking? Is grinding them up and boiling the only option for this potent type. And how do I tell exactly what type of oak tree it is? The acorns are a medium brown colour with a very slight reddish tint. They are located in the Shorthills area of the Niagara region in Ontario Canada.


Green Deane October 26, 2014 at 20:49

You have to unshell the nut, grind the nut up some then soak it changes of water.


Bonnie DiMichele October 20, 2014 at 19:23

Wow, this site has been so helpful . I can’t wait to start processing acorns to make some nutritious treats. Thanks to everyone who gave advice .


George October 3, 2014 at 09:45

This is brilliant and as all “older knowledge”, it should be preserved and practiced as we will not always have the “corner grocery…chain” available. This is sustainable and non-GMO food and for those suffering from Celiac Disease, the acorn is gluten free.

Enjoy the bounty!
God bless.


Ann October 2, 2014 at 22:59

Wow, amazing information! I wanted to know if I could make anything edible out of acorns, and how, and this is the right place. I will share with my gourmet cooking friend, they will be tickled.
Also great info on the USS Constitution, which I got to visit when I was 10, what a memory.
Thank you for sharing.


Eric B. October 2, 2014 at 08:26

What are the options for grinding acorns (as for cold leaching)?

And, by the way, I can’t read the comments. I see where it says “164 comments… read them below or add one,” but the comments aren’t anywhere below. I’m hoping that posting this comment will make them appear.


Stephen Strum September 20, 2014 at 19:31

I would like to read the comments and ask if anyone has been able to order the NewTella from Peter Becker.


David Escobar January 17, 2015 at 08:04

My wife ordered a couple last summer in Germany. We enjoyed it a lot and took a jar to our home in Colombia, South America and shared it with my family. My oldest niece devoured it.
By the way, Colombia has the only Andean Oak species in the world: Quercus Humboldtii, it grows between 6,000 and 10,500 feet above sea level and never loses its leaves entirely. Acorn season can start anywhere between December and February. We are eager to try for the first time our local acorns.


Bryan September 10, 2014 at 00:21

A couple questions ..when you say “The other method is to grind them into a course meal and soak several days or weeks (depending on the species) in many changes of cold water until the water runs clear. These will be slightly bland but good for making acorn flour. (Sometimes the leached acorns will be dark but sweet afterwards.)”, ….beside that phrase you then place a picture of whole shelled acorns leaching- it implies both grinding first as well as grinding after leaching. My insticts say leach first, however, id like you to elaborate. Thanx Deane


Green Deane September 10, 2014 at 07:37

It is as much a matter of taste as efficiency. A rough grind before leaching aids the leaching process. A fine grind would, too, but in subsequent changes of water you will loose some of that fine grind to pour off.


Lisa August 29, 2014 at 04:50

Great article.

But please check your spelling when you translate something. Achorn in Dutch is “eik” and an oak is “eikenboom”. No weird spellings like eychen.. Pleeaaaaseeee.


Green Deane August 29, 2014 at 12:42

Spelling often depends on which expert you consult.


Brown Thum August 10, 2014 at 17:33

Excellent article! Such detailed etymology is rare and i find fascinating. Here in south east Massachusetts our oaks are starting to drop many green acorns, i would like to deprive the squirrels of these, after gathering what would be a Preferred method of processing?
Do acorns need to be brown before leaching or shelling?
how does one store while acorns for future use? A sealed (tupperware) container?


Green Deane August 10, 2014 at 18:59

Thank you. Opinions vary but most think you should collect mostly ripe acorns, which are usually brown


Robin May 27, 2014 at 18:00

I have a question regarding leaching acorns. If I put them in a mesh bag, say an empty bag of oranges, and put it in the toilet tank, do I need to grin them first? Do you grind them to leach and then grind again to bake? Or do they need to be ground to the consistency for baking. If using the toilet tank method, how long do you think it takes? Does it turn the water a tannin color and I’d wait until its clear? Btw, I had a friend who hid his wine bottles from his mother in the toilet tank. She never thought to look there and it chilled the wine. Genius


Green Deane May 30, 2014 at 06:37

A round grind is good, a fine grind is better.


Bortcho Hristov April 22, 2014 at 20:22

Hi Green Deane , Great site I would like to know wich species of oak is native i n Bulgaria, and olso can i make a Acorn flour and feed the Ostrich.


TasteofBeirut April 18, 2014 at 04:33

I found out that acorns were edible last year through my encounters with a local lebanese lady who lives in the mountains; she told me she used to roast the acorns when the village was under a blockade and grind it to drink as coffee. Her humorous comment was that all the others in the village would roast chickpeas (for a coffee substitute) and would be passing gas all day, not her with her acorn coffee!


Jay Dee April 17, 2014 at 13:45

How would I know if the acorns I’ve collected on the ground have aged brown rather than ripened brown?


Green Deane April 18, 2014 at 18:12

In season nearly all brown acorns are good unless they have a hole or crack in the shell. Year old acorns unless well stored are empty or not edible.


European Forager March 31, 2014 at 06:25

Just discovered your site. I was impressed by the fact that you knew the Romanian word for acorn and, furthermore, that you knew about Romanian being “the forgotten fifth romantic language” – few people know that, even in Europe! I have just moved to North America and started researching for plants that I can find here (I use them for medicinal purposes and also for quirky additions to the lunch/dinner menu). My internet search efforts led me to your site – will definitely use it extensively. Already read the I.T.E.M. steps to foraging in a new place and will maintain a safe approach. What I wanted to suggest to you is, since you already go to Greece, you could extend your trip to Romania for a change – it is the forager’s ultimate paradise! There are still vast unspoiled forests and grasslands, producing enormous quantities of: seabuckthorn berries, lingonberries, bolete (porcini) mushrooms, numerous other berries, nuts, roots, you name it! I wish you all the best and I will keep following your website.


Stephen Brummitt March 24, 2014 at 18:54

I was told by a little russian lady that eating acorns can help in regulating blood sugar. She didn’t tell me much more, but has anybody heard of this, and if so can you tell me how many, and what kind is best for this?


Jonathan March 21, 2014 at 10:31

Hi, Green Deane. Thanks for this very helpful article. I was wondering if I cold leached whole acorns, would I have to worry about the acorns sprouting after I’ve stored them if I stored them whole as a food for snacking? Or for snacking should I just use the boiling method? Thanks.


Green Deane March 21, 2014 at 16:10

Shelled and leached acorns don’t sprout. And usually acorns are not leached whole because that takes a very long time (on the scale of months.)


Lisa Doerr February 21, 2014 at 19:46

Hi! First I would like to say that I thoroughly enjoyed and was enlightened by your article! Secondly I have a question please: Are you aware of an aflatoxin affecting acorns anywhere in the US? I have a friend who rehabs squirrels, and has heard of several squirrels in captivity, dying from infested acorns. Any information would be greatly appreciated!
Thank you for your time and information….Lisa


RM McWilliams April 15, 2014 at 04:37

An interesting question. Many foods humans regularly eat can, and often are, infected with aflatoxins with corn and peanuts being among the most common. Evidence of fungal infection of food plants is eaily overlooked in industrial food production and processing, but is often (usually?) apparent if examined closely – which is one of the reasons that Deane warns us to only consume ripe brown acorns that are normal in appearance, with no streaking, off colors, etc.


Cody Mendoza February 8, 2014 at 17:19

Hello all!

I am allergic nuts. Are acorns something I should avoid since an acorn is technically a nut? I have always wanted to try acorns but my allergy has worried me


Stephen Brummitt March 24, 2014 at 19:01

I cannot answer you question directly; but, if I were in your shoes, just to be safe I would ask your Doctor to perform a test to determine this for you; rather than, trying to eat some (with an Epipen handy just incase).


RM McWilliams February 3, 2014 at 13:52

Green Deane – Are you familiar with the YouTube video Arthur Haines produced regarding acorns and processing them for food? He actually prefers the red oaks; he says they keep longer, and can be gathered throughout the winter, wheras the white oaks sprout soon after falling. And he recommends leaching even the ‘sweet’ white acorns.

Anyway, we have used the methods he outlines in that video, and have found it to be pretty easy – and fun!

Please keep up the wonderful work you are doing here on this site, and your videos on YouTube. Thank you!!!


Green Deane February 3, 2014 at 14:05

Yes, I am familiar. That said where I live it is mostly white oaks.


Dakota January 8, 2014 at 22:27

I’m a high school student in Arizona. Several of my friends and I have been collecting the acorns from live oaks at our school, making sure to only collect acorns that had fallen within 6 hours to maintain freshness (We would brush away any that had fallen overnight so we would know) and to keep only the best ones. Originally we kept our stashes in coffee cans. We quickly out grew these and found a 2-3 gallon container that originally held powdered lemonade. This too we filled and dumped our original stash into. However, after coming back from fall break and opening the full lemonade powder container, we were quite surprised. It had a very distinct smell. This was puzzling. The acorns had never been wet, they were kept at a constant temperature, and they were stirred up regularly as well so we don’t think they could have gone rancid on us. The smell was familiar, but we couldn’t quite figure out what it reminded us of. When we did, we realized that it smelled exactly like a red wine. This is confusing to us how that would be a resulting smell. So we wanted to ask you what this could have possibly happened. We have not looked at the bottom of the the container yet because it is so full and deep so we do not know what is at the bottom. We made this discovery only yesterday. Thanks.


Green Deane January 9, 2014 at 00:25

There could be several explanations or combinations. Acorns have tannins which is an important chemical in red wines. It could be just that. Or, you might have some fermentation going on as acorns have starch. You might have a lot of grubs rotting at the bottom or some other creature setting up housekeeping.


Mark A. January 4, 2014 at 21:40

I have a few questions about leaching acorns in natural bodies of water. I’ve heard about collecting acorns, shelling them, grinding them, the finer the better, then putting them in a cloth bag and situating it in a fast moving creek or stream, tied in place. The moving water quickly leaches the acorns by constantly desaturating the water of tannin. It sounds to me like possibly the quickest and most convenient way of leaching acorns.

Would you recommend this method over other methods like boiling them or soaking them? How long do you think they would need to be left in the water, provided it is moving relatively fast? Would it be advisable to boil them after soaking them in this way (to remove any germs picked up from the creek water)?

Thanks for the excellent writeup!


Green Deane January 6, 2014 at 19:50

Boiling wastes a lot of energy. It will take a few days for the tannins to leach out even in fast running water.


John Slattery January 1, 2014 at 00:08

Interestingly, our Emory Oaks in Arizona and Sonora, Mexico are still eaten raw and sold on the roadside in Sonora as they are very low in tannins. The leaves are customarily pointed with less variation than other oaks in our region. The acorns are relatively small with small caps (they are most certainly White Oaks) and the inside of the shell is pubescent.
It’s hard (impossible) to apply absolutes to our wonderful world of plants.


todd December 12, 2013 at 09:27

Hello, I have tried acorns raw all over the eastern half of USA and almost all of them are bitter before leaching. I did find one bur oak in Wisconsin that was as good as a pecan raw. Since then I have tried many bur oaks that were not good. Have you found many trees that were pleasant to eat raw? Also, I planted several varieties of oak (Bebbs and nutty bur etc.) from Oikos tree crops that are supposed to be low tannin but are not old enough to produce yet. Have you ever tried these? Thanks


Green Deane December 12, 2013 at 11:57

There are some that are low in tannin, and a few with none but I’ve never met them.


Foxtrot December 11, 2013 at 16:28

Does anyone have any idea if their are books on organic living? Such as eating edible plants and foliage? * Still not too sure if oak can be used as tea or not… *


Keith December 10, 2013 at 15:02

Wow a lot of comments on this one! Feel free to delist this if you have addressed it…

“There are three general ways to leach acorns. The least common way is to bury them whole in a river bank for a year, which turns them black and sweet, good for roasting.”

By whole I am assuming you mean “with shell” and not “shelled but unground”.

Along the same lines…

“He shells them, leaches them (cold water) and sprouts them before using them to make his NewTella. That helps convert the starch to malt, which is sweet. ”

How do they sprout if they have been shelled? I would figure taking the shell off damages the embryo?


Green Deane December 10, 2013 at 15:52

Yes, they were soaked in the shells in the river banks. At home we soak them shelled. Our German friend is a bit different. He does indeed sprout them in the shell for his purposes.


Jac kie November 6, 2013 at 01:29

Hi from a gloriously war and very autumnal Kiev, Ukraine.

Thanks for the interesting stuff on acorns and especially all the info on winter foraging..the close-up photos are very very useful BUT oh dear…Peter’s site is fine if you speak German !!

Kind regards



Lee Evans November 5, 2013 at 09:23

Hi – I moved out to Comal County, Texas a couple of years ago. When I bought the property there were about a dozen rather nondescript trees here. The realtor said they were “scrub oak” and the branches are subject to a type of blue fungus that can eventually kill the tree. However, they produce lovely elongated acorns with tiny caps. If I stand under any of them when they are in acorn mode, I get clonked on the head with every breeze. The thought came to me that these nuts look like hazel nuts. I had once heard that they were edible. Are the scrub oak acorns OK to process and eat like any other acorn? Seems a waste that they are being used for purposes or annoying me and covering my driveway with crushed nuts.


Green Deane November 5, 2013 at 09:31

As long as it is a true oak, a Quercus, the acorns are edible if not diseased and when leached of their tannins.


Keith December 10, 2013 at 18:02

If not diseased? I was under the impression that there are no plant diseases that are also human diseases? Unless you mean moldy, etc.?


Keith December 10, 2013 at 18:27

To clarify I know that molds and funguses will infect a plant and can be associated with harm like ergot or aspergillus (i think thats the big one in corn, aflatoxin?) but these are molds and fungi not associated with a diseased plant so much as a third party that feeds on the seed. I am not sure though ergot seems like it is feeding directly on the plant. Maybe I’m not so sure as I thought.

The way I was viewing the matter is that things like tomato blight or black spots on the leaves or fusarium etc etc would pose no risk to people who still harvest from the plant. And that the only risk were molds and fungi that colonize seeds and fruits under moist storage conditions after harvest?

Perhaps you can help here.


Laura October 28, 2013 at 22:12

Hi Green Deane,

I recently moved and discovered today that my new home is surrounded by… Emory Oaks! They are everywhere and some are loaded with ripe acorns right now.

Since I don’t have to process these for tannins what is the best way to make acorn meal? Today I shelled them, roasted, then pulverized in a coffee grinder. Any other recommendations?

Also, I am wondering if it is ok to briefly freeze the acorns (for an hour or so) to make it easier to shell them? Or is sun drying the preferred method?


Green Deane October 29, 2013 at 08:14

Hmmm… usuallly things expand when the freeze.


Laura October 29, 2013 at 10:15

Actually I stuck a small batch of acorns in the freezer for an hour. The next day I harvested more acorns and didn’t put them in the freezer.

The acorns that had been in the freezer were much easier to shell and the meats popped out easily while the fresh acorns were stuck in the shells and came out in pieces. I’ll set out the remaining acorns today to dry in the sun and try that method.


Judith October 25, 2013 at 11:32

Personally, I find it a lit easier to go to the Korean market to pick up a bag of acorn starch and make dotorimuk. But then, I live in an apartment and don’t have an oak tree, 😉


Stanton de Riel October 15, 2013 at 09:58

Just a thought for those who leech their acorns rather than leach them: those leeches are probably nutritious once boiled, too!


erica October 15, 2013 at 09:17

No question, just wanted to thank you for this useful and informative thread. Now if this batch of acorn meal on my counter top can ever finish cold leaching I could stop staring at it and make something cool … How does that saying go? A watched pot never leaches?


Aaron James October 15, 2013 at 02:00

hi green deane, this is amazing learning about acorns. i have a question. what about different varieties of acorns? are the leaching rules the same for all types and can you eat all types? i have some here is sacramento CA that are much longer and bigger than the acorn at the top of this page. similar to the the fourth picture down. so those are good too? they have a lot of flesh. it seems like a better choice because they are so big


Green Deane October 15, 2013 at 02:06

If it is a quercus the acorns can be leeched and eaten. The main difference is with some acorns (red oaks) even after leeching the water will have a red tint to it even though the acorns are sufficiently leeched of tannins and ready to eat.


Erika October 7, 2013 at 20:55

Easier cap removal:

I went out today under the White Burr Oak and found a multitude of acorns today! When I go out I have a pot of water and a 5 gallon bucket. When I collect a handful I place it in the water and what sinks I keep and what floats I get rid of. Having the caps moist for a few seconds to up to a minute also made the caps MUCH easier to remove. Once my bucket was full I went up to the house, sat down and began removing the caps. Once that task was complete I again placed the acorns in a bucket of water to toss the floaters and keep the sinkers. (FYI: if you like to fish keep the floaters and wait until the little worms come out…great bait!)
At that point laid them in the truck bed to dry out… tomorrow I’ll de-shell ’em! Hope this helps!!


Steve October 7, 2013 at 10:32

I have read several websites that say that the acorns MUST be ground or crushed before leaching. I was hoping to shell them, then leach them whole to be roasted. Do they HAVE to be crushed prior to leaching?


Green Deane October 7, 2013 at 15:04

No, they can be kept whole and leeched but it takes longer… months longer…and usually they turn black.


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