Brief Acorn Preparation Guide
David Plaisted
October, 2012
When storing acorns, they should be stirred from time to time to help them dry out. Also, the acorn grubs that leave the acorns will go to the bottom of the container and should be removed. The acorns should be stored in a covered container with small holes in the sides and bottom for ventilation. The acorns can be baked in the oven to kill any existing grubs if desired. To shell acorns, heat them in the oven at 350 degrees for about 20 minutes, let them cool a little, crack lengthwise with a nutcracker, and shell with the fingers. If the acorns are moldy, toast them in the oven after shelling them.
After shelling the acorns and removing bad ones, let them cool, rinse them thoroughly, and store them in water for a day or two, changing the water a couple of times a day. Then bake them in the oven at 350 degrees for about 15 minutes to help sterilize them and sweeten them. Many of the inner skins will then be easy to remove. After cooling, put the acorns in water again for a day or two, changing the water a couple of times a day.
Then rub any remaining inner skins off the acorns, where possible. If the acorns have sprouted, the roots should be removed. Put the acorns in a blender with water and blend them until they are broken into pieces about the size of a grain of sand or somewhat larger. Remove large pieces by sifting through a colander. Put the acorn pieces and the water both into a container (or leave them in the blender itself) until the acorn pieces settle to the bottom, and pour off the water above them. Add more water to the acorn pieces, mix, let settle, and pour off the water again. Do this a few times. Save the poured off water, as it will contain acorn powder to make soup.
Then continue rinsing the acorn pieces a few more times, but don’t save the poured off water any more because it will not contain much powder. The rinse water should become almost clear after a few rinses. Then put the acorn pieces in jars, a little in each jar, with plenty of water. Change the water repeatedly in each jar until the water remains clear, changing the water and stirring every few hours, to get out any remaining tannins. This may take a day or so. Now the bitterness should be gone and the acorn pieces should be edible. They can be stored in water in a jar in the refrigerator.
Now, boil some of the acorn pieces for a few minutes, pour off the water, add hot water, boil them again for a few minutes, and rinse them a couple of times in hot water. Then they can be eaten. It may help the flavor to toast them in the oven at 350 degrees until they are nearly dry before boiling them. After boiling, the acorn pieces can be used in bread, as a cereal, or added to other dishes. For cereal, squeeze out some water, and add salt, fruit, and fruit juice.
Acorn powder can be separated from the acorn rinse water obtained after blending. Let the rinse water sit until the powder settles to the bottom. Pour off the water above the powder, add more water, and stir. Let the water settle and repeat this process until the water above the powder remains clear. The powder can then be used as a soup; just heat it with some salt added, but do not heat it too hot. It can also be used in bread. It may help to boil the powder and rinse it again before using it to remove any remaining bitterness.
Oil can be extracted from the acorn rinse water and from the water in which the acorn pieces are boiled. Heat the water to near boiling, if it is not already hot, then let it sit in a measuring cup for a couple of minutes, and then slowly pour a little of it off the top. This poured off liquid will contain a significant amount of oil. Keep pouring as long as the top of the water looks splotchy and non-uniform. The remaining water as well as the rinse water can be sweetened and made edible by storing it at room temperature a couple of days after boiling and then boiling once more to help sterilize it. This water contains some oil and many minerals. It can be used in breads, cereals, vegetables, and rice. The dark powder that falls to the bottom should be discarded.