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Krowtan study results...food for thought

Discussion in 'Tanning' started by Uncle Harley, Apr 15, 2010.

  1. antlerman

    antlerman NTA Life Member #0118

    If salt won't kill bacteria...then I have a question for you.

    Many of us are out hunting mushrooms this time of year. Common practise is to soak them in saltwater over night. Why??

    When a hunter is out in the outback and can't get to a cooler with his kill, we tell them to salt it down. Why?
  2. Marc A

    Marc A Beaver Creek Taxidermy

    I read in Breakthrough yesterday, that salt does not kill the bacteria, but it removes the moister and creates an environment that keeps the bacteria dormant, but as soon as you rehydrate it, the environment is suitable for growth once more. He does go on to say that the salt locks the hair in.

  3. "The major effect of salt as a preservative is that it withdraws water from microorganisms if the external salt concentration is high enough. The microbes would shrivel and die, spores would not be killed but would not be able to germinate. High concentrations of sugar have the same effect. The physical term for this is hypertonic tension. Some bacteria have learned to cope with high salt concentrations and can live in saline waters. Fortunately they are not pathogenic (do not cause disease) so we need not worry about them."

    Dr. Wassenaar
    Curator of the Virtual Museum of Bacteria
  4. antlerman

    antlerman NTA Life Member #0118

    Ok, I except that as a correct answer as it makes sense to me. So it doesn't KILL, but stops or at the very least slows down it's growth. Sounds right. Thanks.

    But it does lock the hair. Do we all agree on that??
  5. Glen Conley

    Glen Conley KARMA GOOSE R.I.P. 2006-2006

    NO! Only like a root vegetable (carrot,radish, beet) in dry ground. Restore moistue levels and you can harvest your hair. By the way, don't forget that a hair follicle will most likely be shaped like a carrot.
  6. antlerman

    antlerman NTA Life Member #0118

    That makes sense too now that you explain it that way, and I reflect upon some past experiences.

    OK, forget I said that!!! LOL But Thanks for correcting my ignorance. You are SO MUCH appreciated Glen.

    Now go get well.

    Note to self........Order more stop rot!!!!
  7. Cole

    Cole Amateur Taxidermist

    Good job guys, you did my work for me.
  8. Salt does not kill bacteria. if that was true the oceans would be pure. Get ocean water in a cut and see what happens!!!
  9. antlerman

    antlerman NTA Life Member #0118

    I guess the only thing it's good for is to make your capes taste better.
  10. Cole

    Cole Amateur Taxidermist

    Good job John, and only 3 days late.
  11. dozier

    dozier New Member

    Static tan's like lutan f takes up to 24 hour's to tan so if you neutralize krowtann 20 minutes thats the only time your tanning . Doesnt sound like much tanning is being done.
  12. TD

    TD My GGG Grandfather John "Tanner John" King b 1820

    The SALT is a WASTE of Time...............
    If you lost Eight Capes with Krowtan............ YOU done somthin wrong.......... Period...............Or your capes were bad to start with.............
  13. Uncle Harley

    Uncle Harley New Member

    Hudson, I apologise for my ignorance but I don't understand " blow out at those levels" I don't do traditional tanning I have you for that ;) That is why I stated " it was my understanding" so I guess my question is, when you are finished and ready to freeze a tanned hide for it to be shipped or at the point the skin is " ready to mount" what should the ph of the skin be. That is what I meant by it was my understanding it should be "slightly acidic" Have I been told wrong? Or have I misunderstood people I have spoke with?
  14. Steve Rotramel

    Steve Rotramel We got some radical rebels in this county!

    5.5 to 6 is awful high.

    The pH affects a lot of factors in the process.

    Like salt, acid acts as a bacteriastat, or in other word reduces the harmful activity of bacteria - namely the excretion of enzymes that damage collagen.

    At 7% salt concentration in the skin, bacterial activity is basically unaffected. 10% slows it considerable, and 14% shuts it down. Thats non-halophilic bacteria for the technicians. Salt in the hide will also serve to reduce hydrolytic damage when you toss the skins into a bucket of acid. I've seen them turn to jelly quick.

    In the case of those who pressure wash, just getting the extra water out by salting may be as important as arresting the bacteria depending on how much time is passing from your fleshing to your tanning operation.

    The pH also affects the reactivity of the collagen. Depending on the tanning chemical being used, it's important to match the pH of the solution to the reactive pH of the collagen for that agent.

    The "blowout" that Hudson mentions means that at higher pH levels, not only does the collagen become unreactive, but the agent itself can even become a different chemical entirely. Aluminum sulfate hydrolyzes above a pH of about 4 and turns into alumnum hydroxide in the form of a gelatinous precipitate. That could affect the tanning agent already in the skin if exposed to those high pH conditions for extended time.

    Remember that the low pH promotes penetration partly because the skin is UN-reactive at that point. Tanning agents can pass freely through the cross section unimpeded by a build-up of agent at the tanning sites. No "surface tan" is happening. But at some point in the process the pH must be brought up in order for the collagen to become reactive and the tanning bonds to take place.

    The "slightly acidic" condition on the surface is probably good news because it means that in the center of the cross section the pH has come up enough for the collagen to become reactive and tanning is actually taking place. That is, if in fact Krowtann has any tanning agents in it. I'm not speaking to that. ;D

    I would venture to say that since your are floating the skins for extended periods, the pH and hence the theorized tanning is happening at close to equal magnitude through the cross section, as the pH in the cross section rises through the reactive window.

    Probably no good reason to go quite that high, but definitely higher than 4 is good.
  15. Uncle Harley

    Uncle Harley New Member

    Hudson, are you saying when they are ready to mount the hide should be in the 4-4.5 range? That is what range it's in prior to Neutralization, After I neutralize shave hand wash and spin dry in the washing machine at that point that I'm ready to flesh If I squeese fluid out from inside the hide it's roughly 6-6.5 ( the scale on my ph strips are in incriments of 1 )

    BTW I still have that fox and elk to send, I got behind a little on my deer.
  16. Well it looks like my banging my head agaiunst thewall for the past few years trying to win this argument is coming true LOL...

    Now if i could only convince you guys to join the anti-Obama impeachment rally
  17. antlerman

    antlerman NTA Life Member #0118

    I'm not a chemist, nor am I a tanner. However, I do know how to follow directions and I have mounted a couple of thousand deer heads over the years.

    Salt drying was always more for a time/convenience factor than anything else due to a lack of freezer space and wanting to get the skins stable.

    Then due to a shoulder injury, I found I could no longer run a round knife without pain.

    I have a local tanner who is excellent. However, he is always covered up to the hilt.

    In an effort to help him help me get my capes tanned, I studied up on pressure washer fleshing and found that I could do that as a way to help along in getting my capes tanned. All I then needed him for was to shave my capes once they were pickled, which he can do since little time is required of him.

    Right from the get go, he told me of loose hairs in the KT'ed capes.
    Then, when thawed out to mount, they literally fell apart.

    We then discussed the pressure washing as potentially being the problem as being too much water left in the hides.
    To extract that water, I started salt drying them. Problem WENT AWAY.

    Now I don't know all the chemical reactions that some of you do. But I do know that the problem stopped.

    I can only surmise that our theory is right based on results.

    Too much water left in the hides!!!!

    Reading Steve's response, I stand on that theory.

    Pressure washing to flesh good, IF YOU REMOVE the water afterwards, so the other processes can take place. Without removing the water, trouble lurks.

    Therefore I stand on my position as to why some have good results with KT. Those are the people who are limiting the amount of water the hide sees before pickling in KT, or any other PICKLING AGENT.

    As for my original response to Harley. Yes, I have tested the pH levels at all stages as I told Harley I had done. I don't claim to exactly know what takes place at those levels, but I've NEVER experienced a problem with anything else, or anybody else's methods until I had the KT problems. To say I did something wrong is about as intelligent as saying I don't know how to walk or ride a bike. NO, I didn't do anything wrong as far as hide care goes. I've been caring for hides a pretty long time. The problem, as I see it, boils down to one thing and one thing only. WATER IN THE HIDE. Salt drying removes the water as my problems went away. In response to Steve about the pH levels, perhaps thats why Brian told me to kick the pH back down with formic acid.

    Now I will give way to you tanners and chemists to shed light upon the subject, but PLEASE don't try to tell me I did something wrong just to save face with your beloved KT. I'm not a truck driver who pretends to be a taxidermist. I'm a taxidermist who drives a pickup truck whose's livelyhood depends on getting satisfactory results from the products I use.

    If a problem exists, it is in the lack of instructions that accompany a bottle of KT when too much water is left in the hide. ie PRESSURE WASHER FLESHING. With THAT said; I suspect that too much water left in a hide would effect ANY PICKLING product, not just KT. So, is the problem KT, or water left in the hide. Well, I definitely believe that water left in the hide is BAD NEWS. As for the KT...............that's a pretty expensive pickle as that's all I know about it.

    Remember, the person who is formulating KT is also a big advocate of Pressure washer fleshing. If you are gonna promote both, then explain both and how to use both in conjunction with each other.

    Based on my own experiences, if your gonna use a pressure washer to flesh, then you gotta salt dry to get rid of the water so other processes can take place. MY OPINION based on my own results. If no one else has had this issue, then kudo's to you. Guess it just sucks to be me then, but I will salt until it fails me, which it never has yet.

    As far as locking the hair or killing bacteria....well I guess we have addressed that, so thanks for clearing that up. But when I salt dry I don't loose hair or have bacteria eating away at it like it was lunch time, so maybe it's a waste of time, but I will keep doing it even if I don't pressure wash flesh anymore.
  18. TD

    TD My GGG Grandfather John "Tanner John" King b 1820

    Antlerman, I have a pretty good idea what went wrong with those capes and its probably nothing you done wrong.I don't believe the pressure washing was the problem.............
    Give me a call if you like and I can explain.............
  19. antlerman

    antlerman NTA Life Member #0118

    I WILL call you Tom, but it will be sometime next week. Thanks
  20. George

    George The older I get, the better I was.

    Tom, that "call me" answer sounds a lot like Laurier. You know there are probably others out there with similar problems. Even if it's an assumption on your part, it's still a step in finding the core of the problem. I know you certainly got my attention with the dumbassed remark about "salting is a waste of time". For thousands of years, salt has been the only constant and now you're going to tell the world all those generations were wrong. Another rocket scientist among us.