Acorns are the small nuts that sprout from oak trees. Most people don’t think of acorns as a food source. However, they are just as nutritious as any other kind of nut. The problem is that acorns contain an abundance of a natural chemical called tannin. Tannin is not harmful but it gives acorns a very bitter taste. Some variations of acorns have less tannin and some have more. To make acorns more palatable, you have to do what’s called “leaching” the tannins out.
There are a few ways to leach the tannins out of acorns. But first, you will want to examine each acorn shell to see if there are any tiny holes in them. This indicates the presence of a worm. You will want to throw them out or use them in your compost pile. Once you have gotten rid of any infested acorns, you need to remove the shells from what’s left to reveal the nut inside. Then it’s best to crush them into slightly smaller pieces and then put them into a large bowl or pot (you don’t have to crush them but by doing so, you expose the inside of the nut which will allow the tannins to leach better). Then add boiling water and let them soak for an hour (don’t boil the acorns in a pot, just pour boiling water into the pot where the crushed acorns are sitting). The tannins will “leach” out of the acorns over time saturating the water, turning it a brownish color. Strain the water out of the acorns and then repeat the process as many times as is necessary until the acorns are palatable to your taste. It make take up to a dozen or more leachings to get them just right. Another way is to put the de-shelled acorns into a fine net and submerge them into a fresh water stream for several days until the water has leached the tannin and bitter taste away.
Once they taste ok, it is very important to begin drying them out immediately to avoid the growth of mold. Drying can be done a couple different ways. You can spread them on cookie sheets and let them sit in the sun, flipping and stirring every so often allowing them to dry all the way through. This will take quite a while. Another way is by smoking them (as you would smoke meat) or putting them in the oven at the very lowest setting again stirring and turning them. You don’t want to “cook” the nuts, just dry them out. No matter how you dry your acorns, you will want to use a cookie sheet to spread them out as thin as possible to allow them to dry faster. Once they are completely dry and have a very low moisture, you can store them the same way you would store any other kind of shelled nut.
While acorns don’t sound like the most appetizing food source, in a survival situation it’s not likely that anyone else will touch them, hopefully leaving you plenty to forage for you and your family.