A year ago, our neighbors the Groths gave us some acorn meal they’d made from wild-gathered acorns. I vowed to try it myself the following fall. It’s turned out very well. It’s even better (we think) than last year’s. The process is not complicated at all.
First, you’ll need to gather acorns. This part is fun. It’s like an Easter egg hunt. Starting in early October, look under large, mature oak trees. The green ones are freshest, but there should be acorns in all shades of green turning to brown. They should feel heavy for their size, and cool to the touch. If they’re black, they’re last year’s acorns and too old.
Discard any ones that have pinholes or rotten tops:
Also discard any that have obvious cracks in them:
Some will look perfect on the outside, but are still rotten inside. I found that about 2 out of 5 acorns were rotten inside. I kept a small bowl to the side for imperfect acorns to toss outside later for the deer. They don’t care about a few extra worms. More protein for them.
It’s pretty obvious which ones are no good.
Cracking open the acorns is easily the most tedious part of the process. It’s great to do while watching a football game.
Most websites I found recommended one of three methods for opening the acorns: a nutcracker, a hammer, or a utility knife. Using a hammer sounded like a great way to make divots in my concrete, and using a knife sounded like a great way to slice a few fingers off. I used a trusty old nutcracker I inherited. It’s literally older than I am, and it still works like a charm. Use the tip of a paring knife to pry the nut meat out.
The meat inside should look creamy white, with no dark patches or veins. If there’s a small imperfection, cut it off with your paring knife. If it’s extensive, though, discard the entire nut.
The nuts will have a thin skin over them. If it’s easy to pull off, do so, but otherwise don’t worry about it. Place nut meat in a bowl of water. This is to keep it from oxidizing and turning brown like apples or avocados.
One site said to not bother with the skinny pointy acorns, because they’re hard to open and there’s little meat inside. On the contrary, if they’re small enough to fit cross-wise in the nutcracker, they’re very easy to open, and there’s plenty of lovely meat inside, and the skins are very easy to pull off.
Now, acorn meat is very bitter. This is due to a high concentration of tannic acids. Luckily, tannins are water-soluble. There’s a cold-water method and a boiling-water method for removing them. The boiling-water method is faster, but it also denatures a certain protein that acts like gluten does in bread, as a binding agent. If you plan on using your meal for baking, the cold-water method is best.
When you have a nice amount of nuts, place them in a blender and add some water.
Blend until you have an acorn slurry.
(If doing the boiling-water method, bring slurry to boil, stir frequently, and pour off tannic water. It will turn a dark brown color. Repeat until meal is no longer bitter, usually after several changes of water.)
Transfer to jars and add more fresh water. Shake slurry and store in refrigerator.
The mixture will settle. The water will be a cloudy beige color. Every few hours, or at least once a day, pour off the water on top and replace with fresh water. Shake slurry and return to fridge. Repeat for 3-5 days, or until meal is no longer bitter-tasting. The water will also be clearer.
Strain meal through layers of cheesecloth or an old clean t-shirt. Squeeze out as much water as possible.
Transfer to a baking sheet.
Spread wet meal out on baking sheet as evenly as possible. Place in oven at the lowest setting possible, usually 175 F. You can also place it outside in the sun to dry.
Stir meal frequently to get wet parts exposed. Meal will turn brown as it toasts. Don’t hurry this step. You want the meal to be very dry.
Place dried meal in a blender and process until fine.
Store in a cool, dry place. The fridge is best as the high fat content of the meal can make it turn rancid if stored at room temperature. Mix 50/50 flour and acorn meal in recipes. My favorite is pancakes. They’re SO filling, and you can really taste the toasted-nut flavor.
Here are three websites I found with detailed instructions: