Steps to Make Acorn Flour
- A bowlful of red oak acorn flour
“Have you nothing better to do with your time?” my friend, a botany professor remarked. I had told him I was setting out to make flour from my myriad of acorns in the yard. I know about many plant uses, but my first hand experience doesn’t cover this endeavor. I blogged about acorn uses previously, so I decided to take that beautiful bowl of acorns and pulverize them into flour. So, I’ll share the process, which can be done in bits and pieces in between a busy schedule.
Extracting the meat from the Shell
- Acorn nutmeats and complete acorns
After collecting of course, the first thing to do is extracting the meat from the shell. I took my husband up on his offer to do this first step. We sat in front of the TV, hammer in hand, a hard, sturdy table in front of us and a couple of bowls. Not exactly how our first Americans went about it I’m sure. The shell is not as hard as a walnut by any means. Just a light wallop to form a crack in the shell is best, then pry the shell open and pick out the nutmeat. Too hard of a smash will make it more difficult to extract the good stuff.
Leaching
- First leaching
- second leaching
- final leaching
My oaks are northern red oaks. These acorns stay on the tree for 2 years. By the time they fall, they are pretty rich in tannin – a bitter substance that the trees use as an insect deterrent. Not at all good to eat, leaching it out is necessary. White oak acorns have less of it. They are only on the tree for 1 year, and would no doubt be a better choice for making flour, but I went with what I have. I filled the bowl full of acorn meats with hot tap water. I let it sit for a half hour after which I saw the water richly tea colored. I drained that water off and replaced it again with warm/hot water. My acorns probably experienced 6 or 7 changes of water over the course of several days; while I was at work, while I cooked, while I slept, whatever. There cannot be too much leaching. Do it until the water no longer turns color. I just checked, stirred, and replaced until I felt it was “good enough.”
Drying
- drying acorn meats on the wood burning stove
- acorn meats on drying rack
Now my waterlogged acorn meats needed to dry out. I spread them out on a screen I’ve used for drying fruit over my woodstove. Getting a bit of heat from the stove spurred the process along. After a day they felt crisp and dry, and when I broke a large piece it snapped smartly apart. Before drying, my nail could be plunged into the meat before it reluctantly separated into two pieces. The sun could also have been part of the drying process, had it made an appearance when I needed it. Any way you dry them would probably work.
Chaff
- gently blowing away the chaff
After drying, I found a lot of the chaffy membrane around the nutmeat had separated. I thought it best to get rid of this. Being brown it probably contains tannin, unlike the whiter meat, and it would not provide any substantive value, and may in fact detract from the final product. I could have tossed my acorns up in the wind, catching the heavier meat in a basket and letting the lightweight chaff fly off. Women have practiced this method for thousands of years in processing grains. I chose a more modern approach as it was a calm and rainy day, and I had a novel idea. My dust buster exhaust port provided just the right gentle blowing power I needed. Back on the drying rack, I could blow the light chaff off and away while the heavier nutmeat stayed put. Worked like a charm.
Grinding
- grinding dried acorn meats with a morter and pestle
- red oak acorn nutmeats before grinding
- fully ground acorn flour
Now that my acorn meat was dry and chaff-free I could grind. Wanting to try the traditional method, I ground some of the meat with a mortar and pestle. Grinding away a little at a time produced small pieces from larger for sure, but it was proving to be tedious. The small pieces didn’t end up grinding down to even course grade flour. Maybe I wasn’t persistent enough, but I was at it for a good 15 minutes. I acquiesced to another husband suggestion that took me far afield from traditional preparation methods – the food processor. With the “grind” button pushed, within 30 seconds I had my complete batch of wonderful coarse acorn flour.
Storage
I recommend an airtight storage container for keeping your flour in the refrigerator. I have yet to determine how long it may last, and I don’t plan to find out, as I expect to bake something terrific from it real soon.
No matter the time and effort, which I wouldn’t regard as too much, I find it completely satisfying to make something useful from nature. That bag of flour just makes me smile. I hope the resulting baked good does. So the questions remain: What shall I make? Pancakes…muffins…banana bread… and will it taste OK?
That was a useful blog post,I count on some more post from you.
Very nice! I saw an explanation of this in a book of Native American recipes at our local library. It was not as specific as yours, though. I appreciate the details. My son and I have collected acorns for years to make acorn flour with, but they end up to hard to grind. I think it was putting them in the dehydrator. I will try your way this year! Many thanks!!!
Your acorn flour came out nice. It isn’t that bad of a process. I start with 5-10 jars of nutmeats and add water to within 2 inches of the rim. Top off the water everyday for about 7 days. This leaches the tannins.