Acorns: the Ultimate Slow Food and Tribute to Autumn
Oak trees and acorns are abundant in our area in California’s northern central valley, the traditional homelands of the Nisenan, Southern Maidu people to the North, the Valley and Plains Miwok/Me-Wuk Peoples to the south of the American River, the Patwin Wintun Peoples to the west of the Sacramento River, and the Wilton Rancheria, the only federally recognized tribe in Sacramento County.
As Cherokees in pre-contact society, we traditionally gathered and ate many nuts, including acorns along with more well known delicacies like hickory nuts, documented in historical texts. However, as we had such vast abundance and variety of foods, acorns were not the staple for us like they were for tribes in other areas. I theorize this is because they take so long to process. We had numerous foods that offered a better return on time investment. As such, acorns aren’t heavily featured in our oral histories and stories.
Indigenous peoples of this area in California though were experts in acorn processing and farming oak trees, using traditional ecological knowledge practices like controlled burning around the most abundantly producing oak trees. This burning helped reduce pest burden.
“For me, processing acorns is a labor of love, a way to slow down and sync up with nature’s seasonal timeline. As a lesson in dedication and patience, acorns will repay you many times over in joy, nutrition, and tasty delicacies.”
I'm what you might call a hobby acorn enthusiast. You’ll find me every autumn walking trails trying to resist the urge to pick up acorns and sharing maple acorn cookies at events. Here, I share my processing method and favorite recipe you might have tried at one of our events.
Acorns are the ultimate slow food. You cannot rush them and they need to be respectfully honored. Acorns have a high tannin content, at levels that are harmful when ingested. The tannins need to be leached before you can eat them safely. Unleached or improperly processed acorns can cause nausea, painful constipation, damage your teeth, and make your mouth feel like felt.
To process acorns, in a nutshell, requires you to collect, dry, crack, grind, leach, and dry. Once properly processed, acorns are healthy, tasty, and fun to cook with!
How to collect acorns:
Identify oak trees in your community. Leaf shape is especially helpful to identify. Different acorns have different tannin levels, nutritional profiles, and size differences. Even among the same species, there is variability. I live among several Blue Oaks and each has a slightly different acorn size. Live Oak acorns are the smallest around here whereas Valley Oak acorns are the largest. I’ve noticed my Blue Oaks have a fattier acorn, which is very tasty in a cookie, while my Valley Oaks produce a more carbohydrate-dominant acorn, which makes a great flour. My favorite to collect are acorns from Valley Oaks because they’re so large. I personally do not bother to collect Live Oak acorns due to their small size, as they would require significantly more time to crack.
Be mindful. Collect indigenously, meaning be respectful of our animal relatives and our relationship to them. Remember that you are a part of a larger ecosystem. Never collect a large portion of the acorns you see – or all of anything. Take only what you need, always. Squirrels, birds, and other animals subsist on the acorns. Only collect when there are vast amounts and only collect a small portion of what you find.
No holes. If you find an acorn with a hole in it, leave it be. It was once the home of an acorn weevil larvae who left behind an acorn you don’t want to eat.
Don’t keep in your home. Some of your acorns will inevitably have weevil larvae in them. They’re harmless, but you don’t want to find them crawling around your home. I keep mine in the garage.
Note: if you collect acorns with young children (it’s a great idea to include them!), check their pockets. They love to secret away acorn treasures.
Dry storage. Lay them out flat in a dry area to cure for several months. Dried acorns are much easier to crack. I use wide shallow baskets.
How to process once dry:
Crack them. I use a small hammer to crack open the shells. Discard the shells and any papery material around the acorn (red oak acorns have papery “tests” or skins surrounding the nut). This step takes the longest and requires patience. It can take the better part of a day to crack open a large haul of acorns. All the better: get helpers that you can trust with a hammer and having an acorn cracking party. Note that you may still find weevils or evidence of past weevil inhabitance. You can discard these.
Soak them. As you shell the acorns, put them into a bowl of cold water. Acorns can oxidize quickly, which can change the color and taste.
Grind them. Once you have all your acorns shelled, grind them up to a grit size. This increases the surface area so leaching can be more effective. I put my acorns into a large tall jar with cold water and use an immersion blender to grind them.
Leach them. I use cold water leaching by storing my acorn-water mixture in a large jar kept under refrigeration. One to two times a day, I strain the water out through a double layered cheesecloth and then replace with cold water. I shake it up and replace into the refrigerator. This process can take 1-2 weeks depending on the tannin level of the particular acorns collected. Once the water is staying pretty clear, it’s time to carefully taste a small amount. If the nutmeat is not bitter, the tannins have been successfully leached. Note that you could also use a boiling water leaching process that is much faster but requires more active monitoring and produces a much darker acorn flour. To do this, you boil the acorns in a large pot of water. As soon as it boils, pour the water off into the sink and repeat until the water does not turn dark and the nuts do not taste bitter. This requires multiple water changes with the number depending on the tannin level of the acorns you collected.
Dry them. Strain the water out through cheesecloth and squeeze as much moisture as you can from the meal. I arrange the acorn meal in a thin layer and put it in a dehydrator at about 100 degrees F until they are bone dry, which can take several hours. You could also put them in a dry warm environment for several hours until dry.
Store them. Acorn meal oxidizes easily. I keep mine fresh by vacuum sealing and storing in the freezer until I’m ready to cook with it.
Cooking with Acorns
You can cook acorn meal into so many delicious and fulfilling recipes, including grits, tasty soups, griddle cakes, corn bread, muffins, and even cookies. Note that there is no gluten in acorn flour, so it’s helpful to use something to bind if you’re making a bread (like regular flour, egg, etc.).
If you’ve enjoyed a maple acorn cookie at one of our CNCV events, this article here takes you through the process and this is the recipe I’ve used (though I substitute more easily found turbinado sugar for the maple sugar and add a healthy dose of maple extract rather than vanilla extract).
If there’s interest in learning more or having a tutorial on acorn processing at one of our events, let me know at cncv.communications@gmail.com. I’d be happy to share more in-person.
For hobby entomologists who are interested to learn more about acorn weevils:
While not pleasant looking, acorn weevils are a fascinating insect. I respect their interesting lifecycle and adaptability to the acorn’s lifecycle – but I like to keep them out of my home. If you’re like me, don’t store acorns in your home and check your little one’s pockets if they’re helping you. Here’s more about their lifecycle if you’re curious.
Weevils deposit eggs inside growing acorns on trees. Baby weevils then live and grow inside the acorns, eating the acorn meat (and digesting it). When the acorn falls to the ground, the weevil knows the time is coming to exit. It will burrow from the inside out and then burrow into the ground around the oak tree it fell from where it will mature. In subsequent seasons, the mature weevil will then climb the oak tree to deposit eggs into growing acorns in a cycle. When you collect acorns, some of the weevils haven’t quite gotten their eviction notice. As you dry them, outside your home, you will find some acorns with new holes, new acorn dust around them, and possibly some crawling grub-like insects. They’ll be looking for dirt to burrow into and sometimes can be found attempting to crawl up walls.
— Sabrina McKinney, CNCV Chair, Communications Director, acorn enthusiast and cookie baker
