I was just in my shop checking the PH of my pickling solution and was wondering?
I understand that you have to maintain the PH around 1.5-2.0 for it to be effective.
I also know that you have to occasionally add more acid to it to keep it at that PH.
Why exactly is it that the PH continues to drop over time?
When you first put in the skins I realize that as the hides absorb the acid that the PH will drop....got that...I think.
But is there a "saturation" point to where the hide will no longer absorb the acid?
And if there is, why would the PH continue to drop?
Does it just degrade in the salt solution, like an opened soda loses it's fizz?
I believe I understand pickling and tanning, but was just wondering about having to adjust the PH.
Can someone shed some light?
Like I said....too much time on my hands.LOL
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try putting a lid on you pickle. seemed to help when I switched to saftey acid
Often adding a hide to a pickle with cause the pH to rise. That's because of various factors, but mostly artificially induced ones in my experience. Borax or DP on a hide is a sure fire bet to raise the pH. Washing the hide with a soap before placing it in the pickle is another guarantee. Remember the bottom, top, and middle numbers on the pH scale. 1= Acid 7-8= Neutral and 12= alkali.
Anything added to the pickle (acid) above the neutral line will bring the pH toward the alkali or "base" side of that scale.
Keep in mind that Formic Acid is evaporative. It gives off fumes and should be used in a well ventilated area. When I used it I ALWAYS had a loos cover on it to prevent any fumes as well to keep it safe from contamination - where something might fall into it. A cover is a good idea for almost any pickle simply to prevent contamination.
Saftee Acid on the other hand is very stable. No fumes - no odor. Normally I mix my pickle at a 1.1 Ph and after placing in the capes or skins in it - it rises to 1.5 PH. After that it remains very stable and I stir it every 1-2 days and periodically check the PH maybe once a week. I constantly keep samples in it over long terms, so I can test something without starting from scratch!
You're right about some slight skin absorption (1.1 to a 1.5)- But after that even Formic should stabilize unless it slowly evaporates over a long time. Try finding out if someone's using Borax during the skinning and fleshing process (TELL THEM TO STOP - use sawdust instead). Do you use a Brick or a Rock (anything) to hold down the pickled skins (DON'T)! Instead - once a day turn your skins over and they will be fine.
I meant rises. I use Saftee Acid on all my skins. I keep them submerged with another plastic container that slips into the first one, then put some heavy stuff in that one to keep the skins in the pickle. Don't use anything other than salt on the hides before they go into the pickle.
Guess my wheels were turning ( although not exactly in the right direction!)
Just curious why it rises.
I can't seem to get it to be stable. The ph rises daily. I only do taxidermy part time and I check the ph daily, but it seems that whenever I check it, it has risen. Not really alot, but around the 2.5 range, I add acid to lower it back to 1 - 1.5 but the next day it's back up. Maybe I'm doing something wrong. Any help would be appreciated. Thanks.
When it freezes - tiny shiny crystals appear in solution. If this happens - warm it up to room temperature and shake the bottle to dissolve the crystals before you use it. This is common during shipment in the winter months and storage in a cold unheated room. If you try to use it without dissolving the crystals - it will not hold its strength. Try to store it somewhere where the temp is at least 55 degrees or higher.
I was going to post on this also. I pickle for 3 to 4 days using Saftee Acid and I noticed my ph rises daily.I have to add about a capful daily to bring it back down.
to keep ph down, make sure your salt content is sufficent. Acid swell will occur.(rubbery feeling)