It is common knowledge Indians ate acorns and were proficient at preparing them, however, how many of my readers know that as recently as 1917 they were being recommended as a source of food during WWI? There are some 50 species of oaks in the U.S. and around 30 of them are found in the Southeast.
A tribe in California stored dried acorns in baskets so air could circulate and prevent molding and used them to make mush and bread, while another also buried them in boggy areas near cold springs and allowed them to swell and grow soft. “They turned nearly black in color, but remained fresh for years”. They dug out a quantity and roasted them.
“When preserved dry in the usual way, the acorns are shucked as needed, and the dry meats, each splitting naturally in two parts, are pounded in stone mortars until reduced to a fine meal or flour. This at first is disagreeably bitter, but the bitter element is removed by leaching with warm water, which in seeping through acquires the color of coffee and the bitterness of quinine. The meal is then dried and stored to be used as required, for mush or bread.”
Eastern tribes preferred the sweeter varieties such as those from the white and chestnut oaks, but did eat any variety in times of scarcity. The Choctaw in Louisiana were noted to make flour from the acorns of the water oak by pounding it and letting water run through it in a basket to rid it of its bitter taste.
*White oaks have round lobed leaves, usually from 7 to 9 per leaf
Of the European countries known to consume acorns, England and France, “boiled acorns [which] were used as a substitute for bread”, and in fact, “acorns were eaten, at least in times of dearth till in the 8th century, when we find in the Regle of St. Chrodegand that by reason of an unfavourable year, the acorns and beech nuts failed.”
*Red oak leaves have pointed lobes, the leaf varies in shape, but always has points on the lobes.
During the war, an enterprising woman used acorn flour in bread baking and wrote that they were useful as a binder when used with corn meal or other coarsely ground gain used in making bread. She thought mush or bread made wholly of acorn flour less pleasing to her taste, but was altogether pleased with the result when combining one part acorn flour to four parts corn meal or white or whole wheat flour.
“The white oak family is the one to look for. This includes the eastern white oak, chestnut oak, and post oak. Their leaves have rounded or irregular lobes that lack any bristles at their ends. Acorns from the red-black oak group have a great deal of tannin. Their leaves have pointed lobes with bristles at the ends.”
The white oaks produce short stubby or round acorns while the red-black oaks produce acorns longer in shape than round. If the acorn’s cap is smooth and shiny, the acorn is from the white-oak family, if fuzzy in appearance, it is from the red-black oak.
In a non-historic setting, when your goal is simply to make flour, it is not necessary to grind the nuts using ancient techniques. Crack the nuts, using a nut-cracker can speed up the process, and cut the nuts into small pieces. Wrap the pieces in cheesecloth, and secure with string. Boil the nut meats in successive changes of water to remove the tannin. The tannin can also be removed by submerging the bundle in water and soaking them for several days, changing the water daily. With either method, they are ready to use when the water remains clear.
The acorn meat will have lost much in color and can be used at that point, or dried in the sun, a dehydrator, or low temp in your oven. When dry, the pieces can be put through a grinder, food mill, or run through a food processor or blender, or even put into a cloth bag and pounded to produce flour.
Method #2: Pound the acorns and remove the hulls. Put the fresh acorn meats in a blender with water and grind them to a pulp. Put the pulp in a towel-lined colander and run water through it or put it in a cloth and swish it in water to remove the tannin. Squeeze out all the excess water and either use the flour, dry it, or freeze it.
I have processed acorns for making ersatz coffee as was done in times of shortage in various cultures.
Sources: National Geographic. Vol. 34. Aug. 1918.
The Operative Miller. Jan. 1919.
Boys’ Life. Oct. 1983. Oct. 1977.
Bennet, Richard and Elton, John. The History of Corn Milling. Vol. I. 1898. London.