Wood ash lye challenge

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Ale

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Hello everyone, as I said in the introduction, I’m new to soap making practise but I’m very interested in the topic. As many beginners, I originally wanted to try wood ash lye soap-making. After some failed experiments I decided to use NaOH, and things begin to go really better. But I’ve continued studying the issue of wood ash lye and now I’ve a very big questions to ask you.
One of the biggest problems related to wood ash lye is the difficulty of determining its composition and concentration. So, my question is: do you think is it possible to create a method for standardizing the concentration of your lye?
And moreover: has anyone thought of determining a sort of “wood ash lye saponification value”, to know (more or less precisely) how much lye of a known concentration we need for a specific fat?

I see that it could seam a bit ambitious as a project, but I don’t think it’s so impossible as it seems. Personally, I would face the problem following three steps:
  • Minimize the differences in the chemical composition between a lye and the other à you must use always the same species of wood and try to burn it always in the same conditions (e.g.: beech wood burnt in a modern stove). Then you can choose to add slacked lime (as described in this Forum) or not, what is really important is to follow every time the same process.
  • Standardize the concentration and find an easy (but precise) way to measure it à That’s the most interesting part of the issue. I see three different ways that you can choose:
    • Choosing a “reference concentration” which represents the optimal force of your lye and attempt to reach it every time. For example, you can use the famous floating egg method to know when your lye is satisfactory, then you measure the concentration with a more precise method. For the following experiments you won’t need the egg anymore, you will simply concentrate your initial lye until you reach the “reference concentration” that you measured the first time. Maybe, the most precise measurement method is titration. But it’s quite complicated. A valid alternative is the hydrometer. If someone is interested but doesn’t want to buy it, at this link (Flag of the planet Earth - Official Website) there’s a project to a wooden hand-made hydrometer. It’s an Italian website but if someone wants, I could provide a translation (I’m not so sure about how reliable it could be, but at least, it’s surely better the floating an egg or a potato). Furthermore, if you have a precision balance you could simply weigh a known volume of solution (this is maybe the simplest method but nobody mentions it; is there any reason?)
    • Boil your lye until you see some precipitate (small crystals similar to salt) on the bottom of the pot. When it happens, your solution has reached the saturation, which means that it contains the maximum amount of dissolved solutes. This amount is always the same (at the same temperature), because it depends on the chemical nature of the solutes (and not on how long you let the lye boil). So, when you see the precipitate, your lye has always the same concentration, and you can simply collect the liquid part (after it has become cold, otherwise it will form some more precipitate) and discard the salt. The final lye produced in this method, will be stronger that the one commonly used, but this is not a problem as you can simply dilute it whit a known amount of water before using it.
    • Someone boils the lye until it’s completely dried, then he recovers the precipitate and dissolves it in a certain amount of water, to reform a lye of known concentration. This way is certainly correct, but I think that it only makes things longer. You could use method B instead and reach the same results.
  • Determine how much lye we need for our fat: That could be a very long process if you want to find the “lye saponification value” of every fat! However, you can at least try to do it for the most commonly used ingredients such as coconut, palm, and olive oil and some animal fats as tallow and lard. You’ll have to weigh a small amount of a single fat, make a saponification with excess of alkali, and then make a titration to determine how much lye has reacted.
So, what do you think? Is it possible to reach a quite reliable result?

Sorry for the long text, and forgive me if my English is not always perfect.
 
Too much.

First of, if I understand you correctly about the saponification value...we already have that so why try and reinvent the wheel?

Second, there are too many variables that go into making “natural lye”, that you will never find an absolute as you noted your self. I had a friend who owned a Subway...he used to get so frustrated because he was required to only purchase from approved sources. So say he ran out of pickles...instead of running to the store for a pickles to tide them over, they had to ‘run out’ of pickles until their order came in. The reason behind it is so that if you go to a Subway in NYC or LA or Chicago or Bismarck...the customer can always count on the pickles tasting the same.
 
Well, about Saponification values I meant that what we already have are values related to pure NaOH or KOH, while wood ash lye is an impure solution of different chemicals.
Obviously I don't think to find precise values that tells you EXACTLY how many grams of lye for every gram of fat; just an indication. Just to know that lard requires ABOUT X grams of wood ash lye while olive oil requires ABOUT Y. And standardizing wood ash lye is necessary because otherwise you can't rely on the same amount measured from one time to the next.
But I accept your advice, maybe I shouldn't take this idea too seriously, I'll just try to do some tests and see what happens.
Thank you
 
Well, about Saponification values I meant that what we already have are values related to pure NaOH or KOH, while wood ash lye is an impure solution of different chemicals. Obviously I don't think to find precise values that tells you EXACTLY how many grams of lye for every gram of fat; just an indication. Just to know that lard requires ABOUT X grams of wood ash lye while olive oil requires ABOUT Y.

Yes, "potash" is an impure combination of potassium carbonate and potassium salt; it lies somewhere between NaOH and KOH when making soap. So when making soap from wood ash lye aka potash, best practice would be to look up the saponification values of both and guesstimate someone in the middle.

And standardizing wood ash lye is necessary because otherwise you can't rely on the same amount measured from one time to the next.

Which can't be because of the number of variables involved in the making potash. I buy my NaOH from Essential Depot, my Olive and Coconut Oils are Kirkland brand from Costco, Palm and Castor Oils are from BrambleBerry, Coconut and Shea Butters are from Rustic Essentials, and Distilled water is Kroger brand from Freddies. I carefully weigh out all my ingredients, prepare and mix my base batter the same way every time. So I should get the same exact soap every time...right? So why don't I?

To start with, I don't know the growing conditions of the nuts and fruits that my oils and butters come from...conditions change from season to season. When said fruits and nut were picked and initially processed can also affect the quality of my oils and butters. Then there shipping times, warehouse times and shelf times...all affect the quality of my oils and butters. Then there is my time and shelving with my ingredients. While I am really good about rotating my stock...I use FIFO (first in first out)...it could take me three months to use and ingredient. And during the Fall/Winter I store the majority of my ingredients in the garage, once the temps hit 80, I bring my more delicate ingredients inside. Sometimes it's cool inside my home (70F), sometimes it's warm (80-90F)...this affects the temperature of my ingredients and how they behave which in turn can affect how long I stick blend, whisk and/or stir. And then there is my mood. This can really affect your soap...are you in a bad mood and beating your soap to death (instead of your spouse or kids) or are you getting down with James Brown?

But I accept your advice, maybe I shouldn't take this idea too seriously, I'll just try to do some tests and see what happens.

Not really attempting to give advice per se, just letting you know that there is more to soap making than science.
 
when making soap from wood ash lye aka potash, best practice would be to look up the saponification values of both and guesstimate someone in the middle.
This is a very interesting information, I never heard of a way to adapt them to wood ash lye.
Thank you.

Only one last thing: you say that, despite your efforts of making soap always in the same conditions (same fat, same temperature...) your product isn't always the same. So why do you do it? Maybe because trying to standardize your method makes everything easier and it allows you to obtain good soap similar to what you expect, or, in case of failure, it makes easier identifying where's the error. It's simply this that I was trying to do, find a method that could be good for me, and maybe for someone else who thinks it can work. It will never make soap making an exact science, but it might (I don't know if it really can or not) help me obtaining some success and satisfaction.
 
Only one last thing: you say that, despite your efforts of making soap always in the same conditions (same fat, same temperature...) your product isn't always the same. So why do you do it?

Because I enjoy it and isn't that the reason why we do anything?

Maybe because trying to standardize your method makes everything easier and it allows you to obtain good soap similar to what you expect, or, in case of failure, it makes easier identifying where's the error.

Or maybe it's just because that's how I roll. I have cooking supplies in one cupboard, and baking supplies in another. I alphabetize my music CDs by genre and artist, my DVDs by genre and title. My yarn is organized by weight. I'm a staff accountant for a CPA firm; I have very specific processes for everything I do. When I first printed out my recipe, it was in alphabetical order...it pleased one sense in that it was orderly, but it wasn't right because it wasn't linear; I don't start with Castor Oil, I start with Cocoa Butter because it takes the longest to melt.

I could make tons of different kinds of soap, but I don't for the same reason I won't be making bath bombs or shampoo or lotions, etc...I like to keep things simple. Which on the face, may seem odd since you can make a good quality soap with just three oils and I use four oils and two butters. I currently make three soaps (regular, goat milk and salt) and lotion bars and I pretty much use the same ingredients for all four items: Regular Soap contains Olive, Coconut, Palm and Castor Oils, Cocoa and Shea Butters, Water and Lye. For my GMS, I leave out the Cocoa Butter and replace water with Goat Milk. Salt Soap is Coconut Oil, Coconut Milk and Salt. Lotion Bars are Cocoa Butter, Shea Butter and Beeswax. I can use the same equipment, I can use the same molds.

It's simply this that I was trying to do, find a method that could be good for me, and maybe for someone else who thinks it can work. It will never make soap making an exact science, but it might (I don't know if it really can or not) help me obtaining some success and satisfaction.

Actually, you said you want to "find an easy (but precise) way to measure it" and my response has been that it's like trying to rope the wind.
 
Okay okay, I didn't want to argue, sorry.
Nor I want to annoy the whole forum with this.
I'm here to learn, and you taught me something saying that my idea can't work. I'll forget it and I'll concentrate in soap making with NaOH, which I already do but I'm at the very beginnings.
Thanks again.
 
Not arguing...discussing. I don't find you annoying. And I didn't say that your idea can't work, just that you were aiming for precision for something that has too many variables. And it's not different than working with NaOH. As an example...there are different saponification tables and there are different soap calculators; obviously nothing is exact or there wouldn't be any differences. But still we make soap.

I'm a believer of 'where there is a will, there is a way' and 'workarounds'. Example...I'm working from home and I log in to my office computer; it's just like I'm sitting at my desk, though the text is just a tad bit smaller. I have full access to all my software and files and that's wonderful, but there is one problem...printing I can't print from my office computer to my home printer. The workaround is to 'print to PDF' and then save the file, then right-click on the file and 'copy', then right-click on my home desktop and 'paste'. It works great when you have a small file and/or just a few files, but sucks big time with larger files or multiple files. When that happens, I just save the docs to a folder, email them to myself, then save and print from another folder. And I solved part of the security issue of having work documents on my home computer, by moving everything to a flash drive and then formatting it.

You know that there are too many variables when it comes to making the potash;...not everyone is going to have access to the same kind of hardwood, not everyone is going to be able to use the same method of turning the hardwood to ash, not everyone is going to be using the same type of water. So look for 'best case'...what hardwoods should be used? And why you can't use certain species. HOW they get the ash isn't as important as the physical nature of the ash...fine ash, course ash, can bits of wood be ground up? And your water source and the makeup of it. And of course, an approximation of yield from xx pounds of ash and xx gallons of water.

Now to test the strength or weakness of your solution...there is ye old egg and/or potato or maybe mixing a cup of oil with xx ounces of potash and leaving it to sit for 24 hours. And of course if you have a weak solution, you need solutions to strengthen it...like boiling it down or running it through the barrel again.

Then of course, once you have an approximation of the solution, you can develop a saponification table for common ingredients.

You have a good idea...don't quit.
 
"not everyone is going to have access to the same kind of hardwood, not everyone is going to be able to use the same method of turning the hardwood to ash, not everyone is going to be using the same type of water."

Oh no, no, you misunderstood me! Or maybe I used a wrong term when I said "saponification valiues". I never thought of finding a number valid for everyone. I'm not mad until that point!
What I thought about were values valid for me and for my lye.
I mean, soap makers in the past had a rough idea of how much lye was required by the fats they used, nowadays we don't have this experience anymore. And this is why who wants to use wood ash lye usually can't make anything good. We must go on "by chance".

When I started making soap, I tried some recipes found on the net which used ash lye, but I can't made anything better than a batch of brown burned lard. Then I converted to NaOH lye, and that gave me many satisfaction. But I'm quite stubborn and I never abandoned the idea of using ash. I realized that the only way to use it quite reliably is regain infos abuot the amount of lye needed for a recipe. And as you noticed, there are many variables which influence this. That's why I thought of a way to standardaze, as much as possible but I know it wouldn't be completely, MY lye. I was asking for opinions, not trying to convince others to use my method. I really thank you for having shared your ideas.
At the moment I don't have ash and I can't either leave my home because of the restrictions imposed by the virus, so I'll put those experiments aside for a while. Maybe in future I'll try do something.
 
Thank you, I did it. There are many useful information on this forum, although a complete description of ash lye soap making seems really impossible to find...
 
When I started making soap, I tried some recipes found on the net which used ash lye, but I can't made anything better than a batch of brown burned lard.

Sounds about right. LOL It doesn't help that if you do an image search for soap make from potash, you lovely white firm bars and that's just not reality when you consider that 1) potash is made from water and burned up wood, and 2) potash isn't the same NaOH.

But I'm quite stubborn and I never abandoned the idea of using ash.

And you shouldn't. If I were twenty years younger and lived out of town or had a wood store or fireplace, I would give it a try.
 
@Ale I love your idea of weighing a standard volume of wood ash lye to determine the density. It sounds a lot more precise than 'float an egg'. I never made wood ash soap, so I have no idea if it'd actually work. It seems like everyone is using the egg test, which might be for a reason (though I'm not sure which reason that is)
I think the idea of establishing a personal saponification value is intriguing as well. Once you've established the sap value for one oil, it should be relatively easy to calculate it for others, thanks to the database of saponification values for KOH and NaOH. The only problem would be to make pretty much identical batches of lye (purity), which sounds very difficult.
@TheGecko I'm surprised by the idea to guesstimate a sap value for wood ash lye, which mainly consists of potash (potassium carbonate, K2CO3) between the sap for KOH and NaOH. Can you explain your reasoning for this advice? Based on the molar masses of the 3 different alkali, I'd expect you'd need more K2CO3 per weight of oil than either KOH and NaOH, instead of in the middle, but maybe there's something I'm missing? Obviously wood ash lye is not pure potassium carbonate, but wouldn't that increase the amount you'd need instead of decreasing it?
 
I'm surprised by the idea to guesstimate a sap value for wood ash lye, which mainly consists of potash (potassium carbonate, K2CO3) between the sap for KOH and NaOH. Can you explain your reasoning for this advice? Based on the molar masses of the 3 different alkali, I'd expect you'd need more K2CO3 per weight of oil than either KOH and NaOH, instead of in the middle, but maybe there's something I'm missing? Obviously wood ash lye is not pure potassium carbonate, but wouldn't that increase the amount you'd need instead of decreasing it?

Unless you are creating wood ash lye in a controlled setting, it's all guess work because of all of the variables which range from the wood, the burning of the wood, the size of the ash, the water used, the ash to water ratio to the size of the holes in your barrel...and why type of barrel.
 
Unless you are creating wood ash lye in a controlled setting, it's all guess work

Well, you suggested a guideline for making a guesstimate and I'm curious what your reasoning for that guideline is.
 
About the SAP value of K2CO3, I made further researches after this thread and I privately ask information to DeeAnna. At the end, I underatood that the theoretical Sap of K2CO3 is 1.73 times greater that the Sap of NaOH.
I know, you measure the Sap of a fat, not of an alkali, what I mean is that if 1 kg of a fat needs 1 g of NaOH to fully saponiefy, the same fat would require 1,73 g of K2CO3.
But wood ash lye is not pure K2CO3, it contains:
- Impurities which will increase the weight but not react with fat. So they will increase the amount of lye needed
- Small percentage of Na2CO3 which has a lower molar mass than K2CO3, and so it will decrease the amount of lye needed.

So, it's not easy to say why should the average Sap of wood ash lye be. I think (but it's just an hypothesis) that the impurities will affect the results more than Na2CO3, but I don't know. That's why, if you are interested as I am on this particular topic, you would need to do some experiments, trying with different numbers
 
Ale, I think that making wood ash lye soap is more of an art than a science, because of the variability of the ingredients. Boiling your lisciva to a standard strength or density is probably a knack perfected through practice and repetition. Here's some info I found that might be useful. Good luck experimenting!
https://tinyurl.com/yagtupzw
 
I still remember my mother-in-law on the farm back in the '60's making her laundry soap from lard and wood ash lye. I don't know how she estimated her sap values but I"m sure it wasn't a complicated formula (well I don't think it was....). I do remember orange spots on the soap, which I guess didn't hurt anything if used for laundry.

I remember something about floating an egg in the solution to test its strength??
 
@mishmish, I totaly agree with you when you say that soap making with wood ash lye is an art, and not a science. The problem is that people in the past knew pretty well how to do it, nowadays we do not know it anymore.
@mtinetti61's mother-in-law probably never heard about "Sap values" and "concentration of a solution". She was an artist, as you said, and she learned it from someone expert, who had known it from another...
Unfortunately, we don't have expert teachers anymore. Sure, we could do better soaps with less work using NaOH, as me and you all do, but if someone wants to try wood ash lye he has only to options, I think. Try somenthing "by chance" (with a very high risk of total failure), or try to work on the information that we have, until he gains a bit of experience.
I know, maybe I'm a bit ambitious, but I'll have enough time this summer to give it a try
 
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