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, Virginia. 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 (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.

Acorn is a combination of "ak" for oak and "corn" meaning seed. The Greeks say velanidi, the Spanish bellota, the French gland, Italians glanda, and the Portuguese, glande. Those come from the Latin word 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 named after the tree it comes from.

At least 450 species of oak world wide, and 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 US 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 (vir-jin-ee-AY-nuh) means North America.

The seed crop from an oak, the acorns, is called a "mast" which means food. 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 is, food fit for humans and pigs versus dry food 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.   

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 and hair inside the caps. Some times those in the first category don't need any leaching, or very little. The rest always do. But first, clean the acorns.

To clean acorns dump them into water and throw away any 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. You don't want to cook them yet, just dry them off and make them a little easier to shell. Upon opening throw away any with worms, unless you like the extra protein. The yield, not counting bad acorns, is 2:1. two gallons of useable acorns in the shell will yield a gallon of nutmeat.

There are three general ways to leach acorns. The least common way is to bury them whole in water 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 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.

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.

The temperature at which you process the acorns at any point is critical. Boiling water or roasting over 165F precooks the starch in the acorn. Cold processing and low temperatures under 150 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.

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 about a week. Then I dry it in the sun, unless there are squirrels about, then in a slow oven (under 150F.)  I end up with a meal or flour, depending on the grind, that will not crumble when cooked. Incidentally, the meat of sprouted acorns are still edible if not green.  Of course, leaching them in a 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.

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.

Whole leached acorns can be roasted for an hour at 350F, 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 store carefully and not be 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 that require leaching are toxic to horses.

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.

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 year.  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.

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.