This Thanksgiving, Consider Cooking with Acorn Flour

Acorn kernels provide a complete vegetable protein and they are full of minerals and vitamins that are absent in refined wheat

Thanksgiving is one time of the year when most Americans eat seasonal native foods. Or at least the squash, pumpkin, corn, turkey and cranberries were all native and seasonal in Massachusetts where the Pilgrims celebrated their first successful harvest in the New World in 1621. What’s rarely mentioned is that Pilgrims also had acorns on the menu, likely in the form of bread made from acorn flour.

acorn Photo by Tomi TapioOak groves are the opposite of monoculture — they can support hundreds of other species
of plants, animals, and fungi that all play different, beneficial roles in the ecosystem.

Over the centuries that followed, Americans abandoned acorns, even though native peoples across the country used the biannual oak harvest as one of their staple food sources. Now regarded as feed for deer, or just a garden nuisance, the acorns from all oak trees are perfectly edible. And the trees are particularly prolific: The oak harvest in North America amounts to more than the annual yield of all other nut trees combined. With over 60 species of oaks spread across the country, it’s worth reviving acorn foods now for several reasons.

This past summer’s unrelenting drought across America’s breadbasket highlighted major failings of an industrial agricultural system that’s based on annual plants like corn, wheat, and soy — monoculture crops that are dependent on massive inputs of water, fertilizer, and pesticides and leave us vulnerable to the vagaries of climate change.

Compared to industrial wheat production, the cultivation of acorns requires one-tenth the water and resource consumption and provides a food source with higher nutritional content. Acorn kernels provide a complete vegetable protein, and they are full of minerals and vitamins that are absent in refined wheat. Oak tree groves are the opposite of monoculture — they can support hundreds of other species of plants, animals, and fungi that all play different, beneficial roles in the ecosystem.

Take one oak-rich state as an example — California would be able to transition to oak agricultural production right away. The state’s area of oak “orchards” is nearly 13 million acres, equivalent to one-eighth of the state’s area. Excluding tan oaks, which are now widely infected with the sudden oak death pathogen (and aren’t technically classifiable as oaks), the other species of oak trees (coast live oak, red oaks, canyon oaks, black oaks, etc) require little to no maintenance and are extremely adaptable. Even if only a fraction of these trees were harvested, the amount of acorns would greatly surpass the annual production of 1.3 million tons of wheat. The crop would require no irrigation, no pesticides or herbicides, and no yearly replanting.

While oaks do take an average of two to three decades to grow to reproductive maturity, there are enough productive existing trees in California to support a thriving acorn market, without depriving the regular diners from the animal kingdom.

Acorn flour is similar to any mild grain — it easily takes on the flavor of other ingredients, says Jolie Lonner Egert, an ethno-botanist in Fairfax, CA who has been harvesting the nuts and experimenting with acorn culinary traditions for the past several years. Egert — whose company, Go Wild Consulting, leads classes on foraging and ecology — has revived recipes for acorn biscuits, pancakes and porridges.

She is hopeful that the gluten-free trend in American cuisine could make acorn flour, which does not contain gluten, more appealing to mainstream consumers who are becoming more and more aware of medical studies linking gluten in wheat products to a range of health issues.

“We need to rethink our relationship with what nourishes us,” Egert says. “Wheat is getting us sick on so many levels, and our addiction to it is now being recognized as harmful to our health, as well as to our soil, our water and our land.” Egert also believes that acorn harvesting, processing and milling can create jobs. “Gathering acorns is relatively easy, so it’s great for people with disabilities, the homeless, or teen workers,” she says.

Every fall during acorn harvest season, Egert employs workers to collect the nuts, paying them $2-$3 per pound collected. One person can gather a pound of acorns in a few minutes, so the job becomes quite lucrative. Each pound of acorns, after going through a 3-day tannin-extracting process, produces about a cup and a half of flour.

The yield from an average tree can be 500 or more pounds in a good year, but the downside to acorn production is that a lean year might yield only 25 pounds of acorns. And there’s no way to predict a lean year beforehand. It also takes an oak tree 18 months to grow an acorn, so the harvests from individual trees only come every two years.

Matt Berry, a field biologist based in the Sierra foothills, explained that the oak harvest varies each year as an evolutionary strategy to defeat predators by constantly varying the food supply. “When you get a big harvest year, all the animals that eat acorns can’t possibly eat them all, so many are left to grow into oak trees,” he says. “Then when the crop is much smaller, that discourages population growth of the mice, deer and birds that eat the acorns.”

Berry has been developing ways to market acorn food products, and has produced a tasty acorn oil with a hand-cranked press that works well a substitute for olive oil in salads and cold dishes. “I think the way we’re going to see acorns in mass production eventually is by getting the high-end foodies interested first,” he says “Chefs are always looking for a new taste.”

Click here for more information on collecting, processing, and cooking with acorns.

photoname Photo by Jolie Lonner EgertAcorn mousse and acorn flour cake

Recipe: Acorn Mousse

2 cups ground and leached acorns (you can use any species of oak or tanoak – I used valley oak (Quercus lobata)

1.5 cups milk

¼ teaspoon salt

2 large eggs

2/3 cup heavy cream

Bring acorns, milk and salt to a simmer in a medium sauce pan over medium heat. Cook for about 15 minutes until acorns are soft.

Process mixture in a food processer until very smooth and if needed, add more milk

Pass the mixture through a sieve and compost the acorn solids

Put the acorn puree in the refrigerator for about an hour to chill

Dissolve sugar in a small saucepan with 1/3 cup water. Bring sugar mixture to a boil over medium high heat until syrup registers 238 degrees on a candy thermometer

Meanwhile put yolks in the bowl of an electric mixer fitted with the whisk attachment. With mixer running on low speed gradually pour syrup down the side of bow. Increase speed to o90high. Beat until pale and fully cool about 7 minutes

Whisk cream in a clean bowl until soft peaks form. Set aside

Stir egg mixture into puree; whisk until smooth. Gently fold in whipped cream. Chill at least two hours and eat.

Recipe courtesy Jolie Lonner Egert. Adapted from Martha Stewart Living Recipe for Chestnut Mousse – January 2005.

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