Tuesday, October 13, 2015

News You Can Use

Maybe. This fall, we have had an incredible crop of acorns in our yard. It seems to happen every few years. This is called "masting", and according to this article in American Scientist it is not tied to weather or climate, but rather seems to be a way of avoiding excess consumption of the crop by not providing enough sustenance for the acorn eaters (deer, squirrels and birds in our area) in the off years. Kind of like the way the periodical cicadas swamp predation by emerging in huge numbers on long, multi-year cycles:

I was amused when I found this article at Maggie's FarmThe Mechanics of Eating Acorns
First you need to get yourself a supply of acorns. Go find some oak trees; they’re the ones with all the acorns that have fallen down around them. I know this sounds condescending and stupid, but oaks come in so many varieties that in autumn this really is the easiest way. It is a bit of a crapshoot, as it is tougher to determine a variety of oak by its acorn than by its the leaf — you can do it, but it is a little harder.
White Oaks framing a Black Oak
We have two kinds of oaks in our yard, the Eastern White Oak, and some kind of Black Oak. There are plenty of acorns under both kinds this year. There are other oaks locally, but these are the most common.

So now we have acorns, but how do you use them?
Some oaks bear acorns so low in bitter tannins that they can be eaten raw. Legend says that California Indians fought over these trees, which makes some sense because one mature Valley Oak can drop 2,000 pounds of acorns in a really good year. A ton of sweet acorns may well be worth fighting over. That said, even “sweet” acorns should be leached to remove what tannins exist in them because several studies show that unleached acorns can make you constipated and can harm your teeth. Of all the species I know of, only the imported European cork oak and the Emory oak of the Desert come close to being “sweet.”
White Oak bark - light gray, scaly
Not ours. Even opening a couple using my teeth left a bad taste in my mouth.
Tannins aren’t the only thing that makes different species of acorn different. UC Riverside Professor David Bainbridge wrote in a 1986 academic paper that depending on species, acorns can range in fat content from 1.1 percent to 31.3 percent, protein from 2.3 percent to 8.6 percent, and carbohydrates from 32.7 percent to 89.7 percent. That is a huge range!
Black Oak bark - firm ridged
 By comparison, wheat kernels are  is about 75% carbohydrate and 12% protein, so you can think of an oak tree as a wheat field in the sky.
What does it mean? It means that in the kitchen you treat acorns from different species very, very differently. A fatty acorn will make a meal, like ground almonds. A carb-rich acorn — like Valley Oak acorns — makes a drier flour, more like chestnut or chickpea flour (acorns lack gluten and so will not rise.)
So what are different acorns like?
White Oak leaves and acorns - note rounded leaves
 ‘Sweetest’ Acorns, meaning lowest in tannin: East Coast White oak, the Emory oak of the Southwest, the Pin oak of the South, the Valley and Blue oaks of California, the Burr oak of the Midwest, as well as the Cork oak and the well-named Bellota oak of Europe. To my California readers, know that there are an awful lot of cork oaks and burr oaks planted in towns and cities here, so keep your eyes peeled.

Black Oak leaves - note points
Largest Acorns: Valley oaks are really big, as are East Coast White oaks. Burr oaks are large, too, as is the California Black oak.

Fattiest Acorns: The Eastern red oak acorns I’ve used have a very high oil content, and I’ve read that the Algonquin Indians used red oak acorns for oil. In the West, the champions are both live oaks, the Coastal and the interior live oak, as well as the tanoak and black oak, which is Quercus kellogii.
A few shelled, raw acorns
So, I should have access to some big, "sweet" (being a relative term) White Oak acorns, unfortunately mixed in with some Black Oaks of lesser quality. Next? Shelling is just work, not knowledge, so I'll skip that. How do you make them edible?
All acorns should be leached with water to remove bitter tannins, which will a) make your mouth feel and taste like felt, b) make you a bit nauseous, and possibly c) constipate you for days.

Getting those tannins out is the big barrier to cooking with acorns. But it ain’t no biggie. With my Valley oak acorns, after shelling I drop the acorn meats directly into my stockpot that was two-thirds full of water. When I fill the pot about a third of the way up with shelled acorns, if I am in a hurry, I bring the pot of water to a boil. The water turns dark. As soon as it boils, pour the water off into the sink and repeat the process. It requires about five changes of water to get Valley oak acorns to taste like chestnuts. I did this all while watching football, and did not miss a snap. Other oaks will require more or fewer changes of water. Choose the “sweetest” acorns on my list above for the least amount of work.

There is a better method, but it takes days. Grind the raw acorns into flour, then mix 1 cup of acorn meal to 3 cups water. Pour this all into a glass jar with a lid and put it in the fridge. Every day you shake the jar, wait 12 hours or more, then pour off the water — and the tannins. How long? Anywhere from a week to two weeks, depending on how bitter your acorns are. This is a good way to leach acorns without using fuel for boiling water, and you do not denature a particular starch in the acorns that acts a little like the gluten in flour, i.e., it helps the flour stick to itself. I go into the full process of cold leaching acorns here.
The better method is too slow for me, although it would undoubtedly work out for Redskins Indians Native Americans. You might even find yourself with some form of Oak Beer.  But after repeated boilings the water kept coming out brown, though after 7 boilings the decrease was noticeable. I settled for 10 boiling even though there was still some brown leaching out).  I got these:
Acorns boiled 10 times

The final product was soft, and vaguely reminiscent of chestnuts in texture and flavor. They did not taste strongly of tannins, but didn't really have much to offer either. But I'm sure Redskins Indians Native Americans didn't eat them for their taste, but their nutritional value.

But wait, there's more!
Once your acorns are free of tannins, you need to figure out what to do with them. Regardless, you need to dry them first or they will rot. Big pieces can be patted dry on a tea towel. If it is hot out, lay the acorns out on cookie sheets and dry in the sun. You could also put them in an oven set on “warm.” You can also put the acorns in a dehydrator set on low heat.

You can also freeze your fresh acorn meal. Store dried flour in jars in the fridge. Why the fridge? What fat there is in acorns will go rancid pretty quick if you left the flour at room temperature.

What you can now do with this flour is pretty limitless. My first success was an acorn flour flatbread in the style of an Italian piadina, which is essentially a tortilla. I then made acorn flour honey cake, which is really very tasty — almost like gingerbread cake. The flour also makes an excellent pasta dough when mixed with regular flour.
After the taste test, Georgia suggested that I might find better things to do than go out and collect a 5 gallon bucket for processing. . . I guess we'll just leave them for the deer, the squirrels and the birds. But it seems such a shame to allow a ton of food to just lay there.

1 comment:

  1. That is the job for the deer and turkeys. They are supposed to turn acorns into protein for you.