Tannic Acid

Submitted by BWS on 9/24/05 at 1:30 PM. ( brandontaxidermy@yahoo.com )

Hello all. I am sorry if this has already been addressed (i found hits in the archives, but not directly answering my question).

Pretty soon i will be preparing and storing acorn flour. What is the most efficient way to use the tannic acid from the leaching vats in a pickle solution? Is there a certain forumla i should follow when using this type of tannic acid rather than crystals? I am wanting to test this method on some scrap hides that i have, and i know tannic acid has been around since the dawn of man-but it is an unfamiliar method for me to use in this way.

Thank you for your input.
Sheila Brandon

Return to Tanning Category Menu

Sheila, I think you're in for a slow process

This response submitted by George on 9/24/05 at 1:40 PM. ( georoof@aol.com )

Not sure how much tannin is in the acorn flour. Back in the dark ages, I boiled oak BARK and leaves to get it. Maybe Glen will have this readily available. Good luck.


This response submitted by BWS on 9/24/05 at 2:41 PM. ( )

I figured since i am going to have the stuff available already (since i will be making the flour), i would try and put the "dirty" boil water to use. I sure wouldn't go out of the way this day and time to make just the acid, but i thought i could kill 2 birds with one stone..lol. I am assuming i could just check the ph of the boil water after i am finished with the acorns?


Sheila dear,

This response submitted by Glen Conley on 9/24/05 at 3:24 PM. ( g.conley@verizon.net )

I think what George was referring to as a slow process was the time for skins to be in solution. By memory, I think it took about five months to produce boot soles...........nice thing about that is that in shrink tests it should pass with flying colors, it's already shrunk. I'm assuming you had taxidermy applications in mind?


This response submitted by BWS on 9/24/05 at 6:37 PM. ( ... )

I wasn't going to use those type tanned hides for mounting (from the archives i learned that it shrank badly). I was going to use it for wall-hangers and leather. Can someone please e-mail me the procedure?

Thank you greatly!

Tannic acid

This response submitted by tannic on 9/24/05 at 9:01 PM. ( )

The tannic acid in the flour will act as your TAN, not your pickle.

It does indeed take 4-12 months to get the skins tanned using the pure veg tan method, the old way. This depends on the thickness of the skins and the desired color of the leather. You have to get the skin to a certain pH and then add the tannins in "feeds" in to your vat, stirring daily. If you add it all at once you get a surface tan and it totally screws up. (it's not forgiving like the usual tans.)

Look up "vegetable tanning" and you'll get more information then anyone can e-mail you in an evening.

Return to Tanning Category Menu