Warning: this post is for entertainment purposes only. There are plenty of published experts out there if you want to read up on working with acorns. Do not stake your health or pantry on the adventures of a foreign language major.
Along the way home from work there is an old green grass median strip between two main roads busy with traffic. It’s an untended space with a few very mature trees. I was crossing the strip lost in thought and suddenly felt crunchy but slippery traction underfoot. What a discovery: three tall old White Oak trees, and acorns underfoot in a solid carpet inches thick. There’s a truckload of fresh acorns in perfect condition. This must be what the farmers would call a “mast year,” when the fruiting trees of a species team up and all produce nuts at once.
Back at home, in the last warm amber rays of sunset I hurried to take a picture of the acorns and leaves. The last light beam was just hitting the window sill. The timing was perfect, the last beam came and went, the picture was a success. But it revealed a line of soot inside the track of the double window pane. I’d never even noticed that before.
Fortunately, the sun this morning hit the window too. This time a scarf made a nice drape for the window track. Only trouble was that during the night, the attractive green-gold acorns had slipped out of their little hats. It took some Elmer’s Glue and a bit of patience to fit them back in. Then we were good to go. This acorn picture is about the upper limit of my cell phone photo taking skills. There are sure to be more artistic ways to portray flotsam that piles up and crunches underfoot, but it is beyond me.
For weeks I’ve been looking around for White Oak trees. For years I’ve wondered about exploring homemade acorn flour. The trick is that acorns have so much mouth-puckering tannic acid that they aren’t edible or healthy until the tannins are leached out. Tannin is after all what manufacturers have used to turn soft skin into leather. Not a target nutrient.Way back in Russian language major days I gathered Red Oak acorns and patiently leached (vs. leeched) them in many changes of water for weeks. One tiny tongue lick of the result was enough to end that science junket and incur plenty of hilarity from the roommates and their suitors.
Later, a library book pointed out that White Oak acorns are a better starting point; they’re lower in tannic acid. Another library book specified that you have to crack open the acorns. The goal isn’t to try leaching tannin out of whole shells. The goal is to get those shells open and harvest the little kernels, and that is your real square one for the leaching process.
Well, how hard can it be to crack open an acorn? Talk amongst yourselves while I go find out.
Back again. It took 3 minutes to split open one acorn using a 5 pound weightlifting Russian kettle bell. The acorn was so smooth and polished that any blow sent it ricocheting off the kitchen walls. So this took several rounds of searching for the acorn under the Bible table and stove and then putting it back on the cutting board. Placing the acorn in a wide jar lid helped to keep it in one place. At last, the acorn split in half, sending pieces everywhere. A quick crawl around recovered the two main pieces. It took a minute to pry out the kernels, tender white nut fragments. These tasted surprisingly pleasant, chewy and starchy and nutlike-ish. Then, the bitterness kicked in for real. Gah! It took another three minutes of tooth brushing with Bronner’s lavender soap to get rid of the taste. So. One acorn, seven minutes.
Next I’ll try putting an acorn in a bag and cracking it that way. Give me a second here.
Ok, progress. Putting five acorns in a clear plastic bag was a step forward. Three good kettle bell whacks apiece made ten acorn halves. The shells are thin and somewhat pliable, and the kernels are soft and waxy-crumbly, so working with an acorn is much easier than dealing with a walnut. But this really calls for a nut pick instead of thumbnails. At least the kernel halves are out, soaking under cold water in a Mason jar in the fridge.
Next question is the inner brown paperlike covering wrapping the kernel pieces. Are we supposed to remove that? Blanching might loosen it, but that would still mean buffing it away from a lot of fragments and halves. The optimistic view would be that when the kernels are ground into silt and soaking in their leaching water bath, the brown paper material will precipitate out.
Update: that brown papery stuff inside the shell is called “testa,” according to Alan Bergo at his https://foragerchef.com blog. He reports that testa is high in tannin; it needs to come off the kernels. For White Oak, once the acorns have dried one can rub the kernels and brush off that layer.
As usual, Captain Wing had a better idea. “No need to stand out there picking up each acorn off the ground. I have just the right short-handled rake. You can rake up all the acorns you want, and we’ll sort them in the garden on trays. And don’t try peeling off each shell. Twelve hours in the dehydrator, and the kernels will shrink down and shells will become brittle and breakable. Put down that kettle bell. Don’t be tasting that water; we have litmus paper. That what it’s for.” Alan Bergo’s blog agreed that dehydrating makes the shells easier and safer to open. The rake idea sounds good, but I still want to inspect each acorn for pinholes first before bringing it home; no point in surprising the neighbors with a knapsack full of emerging grubs.
Will go gather some more acorns and give this a try.