article cited on the Prepper Website details the steps to cold leach acorn flour. These techniques generally do not apply to the white oak fruit due to their very low tannic acid levels, and constitute a delay between you and food in case of crisis. This article discusses how to tell the difference between white and red oaks by looking at the leaves of the oak, and provides some other tips on use of acorns. Leaching the acorns of the white oak group is generally a waste of resources. In the southwest, most of the acorn-producing oaks are of the white oak group. Elsewhere, it might be useful to find a source of white oak acorns in your area for potential future use.
I have an Emory Oak in my front year. If I can beat the javelina to the ripe nuts, they are usually abundant in late October. I've harvested and made flour twice, and it's pretty good. Harvesting can either be done by picking them up off the ground or by placing a sheet on the ground under the trees and gently stroking the branches with a long stick or pole. The gently stroking helps the oak drop only the ripe acorns and helps ensure that only the new crop is harvested. I learned the stroking method by watching our local Apache tribe members harvest acorns.
The shelled kernels are about the size of a shelled peanut, with similar size variations from small to larger. My method is to crack the nuts, briefly rinse the kernels to remove grime or bits of shell, air dry and grind. The shells are thin and most nutcrackers destroy the acorn. I use kitchen scissors to cut off the soft end (the one that was under the cap) and split the shell. I tried cracking them en mass with the nuts inside a towel using a hammer. The results were unsatisfactory, with some nuts destroyed and others not cracked, so back to kitchen scissors. It's time consuming but I don't destroy my food source. If you've found a good way to open them without doing it one-by-one, let us know in the comments!
I use two hand mills when I grind them. The first is a larger Lehman's set for coarse grinding. This reduces the nuts from the size of large peanuts to about the size of wheat grains. I transfer this to my small Back to Basics mill for fine flour. When the nuts are fresh, this stuff is rather wet compared to most grains, so you'll need to check more often for clogging in your mills. I prefer to do this by hand using non-electric means because if I ever really need my front yard acorns for food, we'll probably be in a grid-down scenario.
The flour is sweeter (i.e. more carbs) and has less protein than wheat flour. It has essentially no gluten, so needs some help to stick together for breads or muffins. Eggs or wheat flour can help, if you have them. If you have used mesquite bean flour, it is somewhat similar for cooking. Given this, if I were eating these in serious survival mode, I'd probably bypass the flour step altogether and eat raw or chop roughly to add to stew. If harvesting and saving for future use, shelling and preserving the whole nut kernel is probably the way to go. I may try that this fall and let you know how it goes!