Inge Leonora-den Ouden wrote:I am looking for information on processing acorns, to make something edible or drinkable. That's why I read this thread.
Here in the Netherlands we only have those oaks with high-tannin-acorns (two European species and the American Red Oak). Probably that's why they were used only as a coffee substitute in the past.
I'm in Western MA and am also using Red Oak acorns. I use a one size fits all nut cracker to crack off the shells, but Ive found that the skins on the nut meat don't come off easily and should be lightly smashed to loosen the skins. I use a stone mortar and pestol and kind of hammer the nuts until they are about oat size. Then the skins can be blown away with the breathe while you stir around the nut meat.
I then boil the semi crushed nuts in many changes of water. This part took most of a day the last batch I did. I found that a small bowl of crushed red oak acorn takes about 10 changes of boiling water to really get the tannins out.
After the tannins are out, I will dump them out on sheet trays and spread to a thin layer. Then I dry it in an oven with the door cracked for about 2 hours at 175, turning every 30 min.
(If I was going to immediately use the acorns, I would only dry enough to grind or mash)
Once dry, I will finish into a fine powder with a blender or mortar and pestol.
I so far have only made breads and have been using wheat flour with the acorn flour, so I didn't miss the starch that was lost from the boiling. I just started another cold leaching experiment, using finely ground acorn flour wrapped in a silk cloth. Its sitting in a 2 gal sun tea jar and I am running water through it and changing it several times a day. I'm guessing it will take several weeks at least to get the tannins out this way. I may take some to a nearby stream for faster leeching.
Anyways I think that some of the people that comment about the inedibly may not be leeching out enough of the tannins. The red oak has a lot and it takes a bunch of time to prepare, but once a desirable method is found, it can be done in advance schedule or in bulk to ease the use of these little wonders.