The Neglected Harvest: Acorns
By Matt Powers


With 41 million Americans facing hunger currently, the search for solutions is constant – all but a scarce few are overlooking the abundant yet neglected harvest many communities fail to see outside their doorsteps despite their very real hunger. America’s acorns could be feeding millions – directly and indirectly. Acorns have long been eaten by people and animals all over the northern hemisphere – there’s nothing to stop us from eating them again or using them to raise animals. For example, some of the finest prosciutto comes from acorn-fed free-roaming Iberico pigs in Spain. Instead of acorns being a landscaping nuisance, we need to embrace them for what they are: hyper-local, nutrient-dense, gluten-free, perennial, wild-foraged food!

The Miracle Acorn

Acorns don’t come every year: instead they form masts, massive yields that occur in intervals every two to a dozen years. You might have a nut tree in your yard like a pistachio that alternates the years it fruits. This large yield allows for an easy harvest and processing, which requires only drying and leaching of the tannins. It is rare, but sometimes an oak tree grows acorns that has no tannins – it is a sweet acorn! We all can gather our own acorns, process them, and eat them or feed them to our animals. You don’t need to be an expert on acorns to gather enough acorns for an entire year within a few hours with a rake and dustpan. It truly is a natural abundance during those mast years!

Imagine gathering all your flour needs for the year in one afternoon. It’s similar to the way hunters take home one or two deer in a few weekends of hunting and save on buying meat from the store the entire winter or even next year. Natural abundance has that kind of ability – it’s what gave early humans the free time to imagine, reflect, and invent new ways of thinking and being. We could be leveraging natural abundances that are already in place to fight hunger and free ourselves from annual grains by embracing the perennial foods already in place.

Living on Acorns

For several seasons now, Winfield Farm’s Bruce Steele has been only eating food grown and raised on his farm as part of a challenge that he and a friend took upon themselves. He relies on acorns in his diet, and he’s planning on scaling up even more by growing oak trees to raise acorns to feed his Mangalitsa pigs which he sells for meat and uses their lard for biodiesel to run his farm in tandem with solar power.


Bruce Steele shares his insights here on drying, leaching, processing, researching, and using acorns:


After collecting acorns you need to spread them out and dry them. This process takes a couple months. Acorns that are cracked or acorns that try to germinate will spoil and need to be thrown away. Sun drying is ideal, but acorns need to be moved indoors if rain or fog threaten. Acorns that fall early in autumn have better drying conditions than acorns that fall later during rain season. Acorns that have dried will separate from the shell and facilitate ease of use with the Davebuilt nutcracker. The nutmeat needs to be separated from the shells, a somewhat time consuming part of processing acorns, but it is during this process that you need to sort out any spoiled or moldy nuts.

The next step is rehydrating the nutmeat overnight with some water in a refrigerator. They can then be a put into a blender (one cup meats and two cups water) and blended into a wet cornmeal consistency. The nutmeat and water are then transferred into one quart mason jars and put back into the refrigerator. Once a day, pour off the liquid but be careful to not pour out the white layer of starch that floats above the blended nutmeat – you can use a natural fiber cheesecloth to do this. After you’ve drained off the tannin-rich liquid, add fresh water. Repeat this process until when you hold a bit of the acorn mush in your mouth, it isn’t bitter at all. This can take 3 – 10 days depending on your acorn type. This is called cold water leaching.

Different acorns require different amounts of time for leaching. Holm oak needs fewer days of leaching than native California oaks. If you can locate Holm oaks, I would suggest using them. There are many different types of oak trees and acorns – you need to experiment with each type to determine how long they take to remove the bitter tannins. This step is critical to making acorn flour for human consumption. If you have access to California black oaks that live at above 3,500 feet in the Sierra then you should try to collect and process them because they were favored by Native American tribes.

I have processed California Live Oak, valley oaks, cork oaks, holm oaks, and Gambel oaks from Arizona. Black oaks are a good species to target. In Arizona there is a species of sweet oak with very low tannins called Emory oaks. All of these western oak species can be processed into acorn flour, but some take more leaching time than others, and some just taste better when you are done.

Once you have finished the leaching process, pass the water, white starch, and nut meat through a strainer, and keep the water: it will have the white starch in it. You can wait till the starch settles and decant the water. This is the part of acorns that the Koreans use for Dotorimuk (Korean acorn jelly). It is very useful as a thickener and can be utilized much like cornstarch. The strained nutmeat can be spread thinly onto a cookie sheet and sun dried. Once dry, a flour mill will turn the dried nutmeat into acorn flour.


Bruce’s methods are just one way to process acorns for food purposes – there are several other ways to do it: you can even leave the acorns in a net bag in a stream for 3-7 days to let the tannins flow out that way! Learning to use your acorn products requires some experimentation in various recipes. Acorn flour has no glutens and will not rise like wheat flour. Some people mix it with wheat flour for cakes or cookies, but if you are using it as a gluten-free flour, then you need to experiment with using beaten egg whites to lighten cookie, cake, or pancake recipes. If you don’t want to use eggs, you could use any other binder you choose. Mark Salter, acorn aficionado, has tried and likes tapioca starch, arrowroot starch, and even cattail starch!


The Oaken Future

While you may not have an oak tree in your yard, your area likely has some, and if not, there’s likely an indigenous edible equivalent in your area that is being similarly neglected. The native oak savanna is an assembly of interrelated species, not just the acorn-bearing canopy tree. As we embrace the cornerstone of an ecosystem and food system that worked in concert, we will see the return of other beneficial species for medicine, fiber, and food. By supporting the oak savanna and native biodiversity, we support so much of what the oaken savanna generated and protected.

When you crack open an acorn, you are participating in a long tradition that spans the northern hemisphere, and one that can open the door to end hunger, break off our reliance upon industrialized agriculture, and embrace an abundant world of wild foods and foraging abundance!


Here’s the article as a pdf, as seen in Issue 09.

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