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In the recent Stew-Mac catalog, there is a "trade secret" tip about adding meat tenderizer to the water of your steam source when steaming off difficult necks. I was intrigued and did some research and thinking (always dangerous). I am presenting what I found and thought so folks have more information, not with the intention of saying this practice is not a good idea. It probably works as advertised and may not pose any risk at all.
Meat tenderizers contain one of two protease (protein destroying) enzymes. Either Papain, from papayas, or Bromelain from pineapples. They tenderize meat by breaking down the proteins that hold it together. Hide glue is mostly animal protein so it is not surprising that it also helps loosen up joints held together with HHG.
Plants, and particular woody plants, also contain proteins. Lignan for instance, has a significant quantity of proteins in it as part of its structure. So I wondered if Papain had a detrimental effect on wood due to its protease action.
As it turns out, it probably does. I found one patent and some scientific articles related to using Papain to break down wood pulp lignans to make smoother and better quality paper. I didn't dig far enough to determine amounts of Papain required nor efficiency of Lignan destruction.
So a couple thoughts of mine on meat tenderizer and neck removal.
- It may do some amount of damage to the wood. I have no idea how much or if the damage it does is actually less than would be done by the extra steam required for a difficult neck without the tenderizer.
- It may soak into, and be left present on the surface of, the gluing surfaces of the joint. Could this residue, over time, reduce the strength of the hide glue used to reglue the neck? Maybe. Maybe not. Certainly seems possible but maybe not probable.
- Would it be possible to use meat tenderizer in water, not steam, to loosen any HHG joint without steam or heat? Could you soak a joint in water/tenderizer and have the glue just dissolve? Maybe. The questions above become more pronounced in my mind with this technique. Might be worth a try though... a syringe full of liquid papain meat tenderizer into the neck pocket, wait 3 hours and pull....

Sorry for the rambling thoughts and information. If I had any time I would do some experiments.
I hope the information is helpful to someone.
Dave

Saw that in my new catalog. Bet it works great.

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"Act your age, not your shoe size" - Prince

I saw that too and thought that was kind of clever. Regarding whether papain or bromelain would damage the wood, I doubt it because those enzymes don't break down lignin since lignin isn't a protein. Papain does break down a protein called extensin which crosslinks lignin molecules to some extent, so it could have some indirect effect on lignin by affecting how extensively lignin molecules are linked together. However, lignin is not the major molecule contributing to wood strength, so such an effect would likely be very very minor.

I also doubt that any residual enzyme would affect an HHG joint since the joint would be dry and dry HHG would likely be a very poor substrate for the enzyme. Also, the activity of the enzyme (even in a wet joint during glue up) would probably be low to nil at the temperatures guitars and luthiers operate in.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

Sorry, but as we distil water to purify it, leaving any dissolved impurities/substance behind in the still, I can't understand how this meat tenderiser added to the steam generator could make the slightest bit of difference to the steam coming out the end of the hose/needle? Smells of snake oil to me.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I saw that too and went to the corner butcher in the town where I live and got a couple of filets and went home and made them on the grill. Yum, yum, great stuff especially with fresh Florida sweet corn.

PS: The glue in a dovetail is only insurance. The heavy lifting work is done by the mechanical nature of a well made and fitted Dovetail. As such even if residue from the meat tenderizer remains and weakens the glue I don't see any consequence of this beyond maybe speeding up the next reset 30 years or so from now.

During a reset the old glue is removed anyway and likely any residue as well as the dovetail is rebuilt with new shims, etc.

Your neighborhood butcher is also a great place to source cow femurs from hopefully free ranging cattle that use their legs which makes for excellent nuts and saddles after spending a couple seasons in the yard to let nature eat most of the creepy crawlies and fat off it.

I'm looking forward to Dan doing a trade secrets on Mexican Strats so I can go get some tacos. I love tacos.....

That was my first thought too. I guess even triple distilled vodka has some impurities left in it but still... pun intended.

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I'm looking forward to the article on Japanese Strats, a plate full of sushi.

That's kinda' what I was thinking. Are we saying that the tenderizer boils out with the steam? That seems unlikely to me. It seems more likely that the salt is raising the boiling point of the water making the steam hotter.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Distillation isn't perfect. While most contaminants are left behind, there are still some that carry over with the steam.

Some alcoholic spirits are distilled multiple times to remove as many of the contaminants as possible.

With liquids yes, multiple distillations to remove liquid contaminants, (mostly oils with alcoholic spirits), which are liquids and hence produce vapors at water's boiling point.
How much salt goes out with the steam when you boil salted water, or sugar when you boil toffee?
Any solid carried over with the steam would have to have a vapour pressure at the boiling point of water, not a property many solids have.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

a solution looking for a problem after a few thousand necks I use tap water ( I am on a well )
steam works every time. Martin is using tap water

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Interesting discussions nonetheless. Even if only for the sake of discussing. I have to admit that I have not watched the video yet but. . .

As I said before, I'm dubious that the tenderizer is actually in the steam (or at least enough to make any difference), so it makes me wonder why it is effective. Or even if it is effective. Often we get a result despite the fact that our hypothesis has nothing to do with what caused the effect. Sometimes we only think we see an effect.

Maybe it is working as advertised, maybe the boiling point is raised enough to make the steam hotter and slightly more effective, maybe 100 other things. I have to wonder though, if this is being used for stubborn necks, is this a case where you steam the neck and it doesn't come off so you add meat tenderizer to the steamer. It seems like steaming a joint and waiting a few mins. then steaming it again would probably be about the same.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Even if the tenderizer is present in the steam, it's unlikely that the enzyme would still have any activity after being subjected to boiling temperature.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

God, I love this group

Steve

I certainly ain't got nothing against that as an idea.....

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I haven't see the article yet (was it one of Mamie's?), but yes, this is an old, old method for loosening hide glue joints. Bromelain is what does the work, and the simplest and most available source for it is meat tenderizer.

I've not heard of it being used in a steam pot before, but that's interesting. I never considered trying it for two main reasons. First was the uncertainty of how much of the bromelain would even make it in to the steam stream. Second was that in my experience the heat/steam itself works on a much faster scale than bromelain in terms of denaturing and loosening up the collagens, so I never felt it would have much chance to do it's work or have any significant effect. I've only ever used it in dissolved in warm water in cases where aggressive heat and steam seemed less appropriate, like removing some finished classical bridges, or separating plates from rims.

I have had concerns over contamination of remaining glue residues, or possible effects to the cellulose fibers of the wood, but I really don't know if this is a significant risk or not. I do know it's an age old technique, which in absence of hearing reports of damaging side effects is reasonable support that it's probably not an issue. Then again, there's always the possibility that there may be side effects that I just haven't personally witnessed or heard of.

Guess I'll have to find the catalog and read the article.

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Eschew obfuscation, espouse elucidation.

This works on stubborn joints too.

This may be a first on the OLF. We've never had a video here before of someone beating their meat.........

A technicality to be sure, but that wasn't his meat he just worked there.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.