Dual lye castile

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DeeAnna

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Hey, liquid soap makers, here's a new thing to make with your KOH --

I have been reading Anne Watson's "Castile Soapmaking" book. She discusses the issue of castile (100% olive oil + NaOH) soap forming that slimy gel we all love to hate (aka snot or slime) and the related problem of the soap not lathering well. To help combat these disadvantages, she suggests making castile soap with 5% KOH and 95% NaOH.

Intrigued, I put it on my to-do list. Last weekend, I made a small batch of "mock castile" soap using 100% high oleic safflower oil, 5% KOH, balance NaOH, 40% lye solution concentration, 3% superfat. My personal calc includes estimates for the actual purity of the lyes, so there's less chance of extra "hidden" superfat in my soap compared with recipes made with most online calcs.

By golly, Anne's suggestion works pretty good.

I compared this week-old soap to a 2 year old 100% OO soap by washing my hands in cool water. The OO soap immediately formed the classic ropy gel and small amounts of creamy lather. I could put my hand flat on the wet bar of soap, pull it away slowly, and the soap would form slimy ropes of gel 1 to 1 1/2" long before they broke.

The young HO safflower soap doesn't make any snot at all. It lathers easily with a nice amount of fluffy bubbles mixed with a creamy lather that has a slightly slick, syrupy quality. This slick, syrupy quality of the young soap's lather is similar to that of the older castile after I worked to get its lather developed.

The soap with 5% KOH is not at all soft or sticky. It unmolded and cut nicely 12 hours after the soap was poured. It looks just like a normal bar of NaOH soap. I found myself wondering how 10% KOH would change a high oleic soap, whether for better or worse. Or whether 5% to 10% KOH would improve the amount and quality of lather in tallow or lard bar soaps -- in other words, soaps high in palmitic + stearic acids.

Some of you might wonder why I used HO safflower if the point was to make a castile. A couple of years ago I made a 100% OO soap and a 70% high oleic safflower + 30% lard soap and compared the two. They both made the same slimy gel and the same low level of lather when hand washing, so I concluded a castile acts like a castile because of the high oleic acid content more than anything else. I don't have any OO around that I want to use for soaping, but I have plenty of HO safflower. My earlier experiment made me comfortable with this substitution.
 
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snappyllama

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That is interesting! With the brick-hard bar that my Castile makes, I don't think 5% KOH would be any problem at all and anything that cuts down the slime factor is awesome.

Next time I make Castille, I'll have to try it out. Thanks for the suggestion!
 

DeeAnna

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It still has that odd castile syrupy-ness to the lather, but I doubt the average soap user would pick up on this. What they would notice is the soap makes lather a faster, it's more bubbly, and there's no slime. I'm curious to see how the soap does as it cures.

A tip for those who masterbatch lye -- I used a 50% NaOH master solution to make this soap and had to add the extra KOH somehow. I experimented with adding the KOH directly to the 50% NaOH solution and wasn't surprised to find that didn't work very well -- the KOH flakes didn't dissolve. I then added enough extra water to the lye mixture to equal the KOH weight and the flakes dissolved fine. I'm sure if I had made a 30% or 35% NaOH solution, the KOH would have dissolved fine without any extra water. It's just when the solution is near saturated that this will be an issue -- be sure to add enough extra water for the KOH.

I remembered this evening during supper -- there was a gal with the screen name of Sistrum who talked about using 10% or so of KOH in her bar soap recipes when she was active here a couple or three years ago. I should look up her posts.

IL -- I'm glad I could tempt you with this! :)
 

DeeAnna

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If you've got the KOH on hand, this change is easy to add to any recipe, although I think high oleic soaps (olive oil) and high stearic-palmitic soaps (lard, tallow) will benefit the most.

I recently added an article to my website about how to properly calculate the weights of NaOH and KOH for a dual lye recipe: http://classicbells.com/soap/dualLye.html
 

Arthur Dent

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Very interesting indeed. This reminded me to test my 100% HO safflower soap I made last October following a discussion with Obsidian. It's whiter than any other soap I have made, totally without any smell at all, completely DOS free, and rock hard. It does indeed give the ropy slime that everyone talks about from castile, though if you work at it a while it turns into a nice creamy lather. If 5% or so KOH would get rid of the ropy slime this would be a pretty nice soap. I think it's time to order some KOH.
Thanks very much DeeAnna!
 
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DeeAnna

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It's an elegant solution to the problem, and I can't think of any other solution that really solves the problem of snotty castile except to make a bastille. And then it's not castile anymore.

An old-time Castile soap would have been made with a lye solution made from the ashes of seacoast plants. Because these plants had to deal with a lot of salt from the ocean, the lye solution had a lot of sodium in it, but there was still a goodly amount of potassium, since plants naturally contain potassium in their tissues. So the original castile would have been made with a mixture of sodium and potassium alkalis. Maybe this dual-lye recipe is taking castile back to its roots?
 

mzimm

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The soap with 5% KOH is not at all soft or sticky. It unmolded and cut nicely 12 hours after the soap was poured. It looks just like a normal bar of NaOH soap. I found myself wondering how 10% KOH would change a high oleic soap, whether for better or worse. Or whether 5% to 10% KOH would improve the amount and quality of lather in tallow or lard bar soaps -- in other words, soaps high in palmitic + stearic acids.
Thanks so much for posting this.....I feel some experimenting coming on, lol. My oils stock is heavy on the tallow, with more coming soon after rendering a grass-fed beef we're buying in to. I would dearly love to up the percentage of tallow in my recipes if I could only improve the lather somehow.
 

DeeAnna

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Since this is my first experience with adding KOH to an otherwise normal type of bar soap, I can't say for sure whether a bit of KOH will help a tallow or lard soap lather better. But I do know potassium soaps are more water soluble than the equivalent sodium soaps, and being more soluble is related to making more lather.

As the KOH dosage goes up, it will eventually make the soap unacceptably soft, more like wax or clay. I know 40% KOH makes a soft soap from watching the experiments Kevin Devine did with his shave soap (look for Devinely Yours videos on Youtube). But 5% KOH seems to be a safe dosage to try and even 10% might be fine. Anything over that is going to be an experiment.
 

Barbsbreakingbath

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Castile

Hey, liquid soap makers, here's a new thing to make with your KOH --

I have been reading Anne Watson's "Castile Soapmaking" book. She discusses the issue of castile (100% olive oil + NaOH) soap forming that slimy gel we all love to hate (aka snot or slime) and the related problem of the soap not lathering well. To help combat these disadvantages, she suggests making castile soap with 5% KOH and 95% NaOH.

Intrigued, I put it on my to-do list. Last weekend, I made a small batch of "mock castile" soap using 100% high oleic safflower oil, 5% KOH, balance NaOH, 31% lye solution concentration, 3% superfat. My personal calc includes estimates for the actual purity of the lyes, so there's less chance of extra "hidden" superfat in my soap compared with recipes made with most online calcs.

By golly, Anne's suggestion works pretty good.

I compared this week-old soap to a 2 year old 100% OO soap by washing my hands in cool water. The OO soap immediately formed the classic ropy gel and small amounts of creamy lather. I could put my hand flat on the wet bar of soap, pull it away slowly, and the soap would form slimy ropes of gel 1 to 1 1/2" long before they broke.

The young HO safflower soap doesn't make any snot at all. It lathers easily with a nice amount of fluffy bubbles mixed with a creamy lather that has a slightly slick, syrupy quality. This slick, syrupy quality of the young soap's lather is similar to that of the older castile after I worked to get its lather developed.

The soap with 5% KOH is not at all soft or sticky. It unmolded and cut nicely 12 hours after the soap was poured. It looks just like a normal bar of NaOH soap. I found myself wondering how 10% KOH would change a high oleic soap, whether for better or worse. Or whether 5% to 10% KOH would improve the amount and quality of lather in tallow or lard bar soaps -- in other words, soaps high in palmitic + stearic acids.

Some of you might wonder why I used HO safflower if the point was to make a castile. A couple of years ago I made a 100% OO soap and a 70% high oleic safflower + 30% lard soap and compared the two. They both made the same slimy gel and the same low level of lather when hand washing, so I concluded a castile acts like a castile because of the high oleic acid content more than anything else. I don't have any OO around that I want to use for soaping, but I have plenty of HO safflower. My earlier experiment made me comfortable with this substitution.

Deanna, did you have to stick blend it forever? Just curious
 

Susie

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Thanks so much for posting this.....I feel some experimenting coming on, lol. My oils stock is heavy on the tallow, with more coming soon after rendering a grass-fed beef we're buying in to. I would dearly love to up the percentage of tallow in my recipes if I could only improve the lather somehow.
Are you talking about bar soap or liquid soap here?
 

ngian

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Well this is also on my to do list of experiments, and I am glad to read your review DeeAnna on how the 5% KOH helps with lather in a recipe without any Myristic and Lauric fatty acids.

And this tip was firstly presented by Evik (the curious soapmaker), that Anne Watson is also crediting in her book:

https://www.facebook.com/CuriousSoapmaker/posts/995497590524116
 
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mzimm

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Are you talking about bar soap or liquid soap here?
I assumed DeeAnna was talking about bar soap in her post, so yes, I was talking about tallow bar soap, too. I'm one of those who feels she must have the full lather experience in order to really enjoy a bar of soap, but my tallow soaps have all the qualities of great soap EXCEPT exceptional lather.
 

Susie

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I assumed DeeAnna was talking about bar soap in her post, so yes, I was talking about tallow bar soap, too. I'm one of those who feels she must have the full lather experience in order to really enjoy a bar of soap, but my tallow soaps have all the qualities of great soap EXCEPT exceptional lather.
OK, I can speak to tallow in bar soaps, I have actually made those.

When I rendered tallow, I made several batches of soap at varying amounts of tallow. One thing they all had in common was good lather of big bubbles. I used 5% Castor Oil and 1 Tablespoon of sugar per batch. But I have soft water.
 

mzimm

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OK, I can speak to tallow in bar soaps, I have actually made those.

When I rendered tallow, I made several batches of soap at varying amounts of tallow. One thing they all had in common was good lather of big bubbles. I used 5% Castor Oil and 1 Tablespoon of sugar per batch. But I have soft water.
Thanks Susie! Adding sugar is something I've seen and considered, but haven't tried yet, so it too goes on my list of experiments. Castor oil helps, but honestly I think our biggest problem here is the hard water. We have well water high in iron deposits, which no amount of Culligan tweaking seems to help with. My "city folk" friends think my tallow soaps are great, and have no problems with the lather, but for us here at home on the farm, I'm still looking.
 

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Yeah, you're going to have to address your hard water first. Before sugar or anything else will help. There are several threads that talk about adding EDTA and other additives to help with lather and soap scum.
 

DeeAnna

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Barb -- This batch traced faster than I would prefer. I don't think that was from the KOH. It was a very small batch of soap, so I may have been more heavy handed with the SB than I should have. Also I was using a 40% lye solution concentration (I originally wrote 31% in my first post -- error has been corrected), and that would have caused the soap to trace faster. And last but not least, my HO safflower is older, so I imagine the free fatty acid content may be higher, and that will cause faster trace.

Nikos -- Thanks for tracing the credit back to Evik, the Curious Soapmaker. I don't think Evik is the originator of this idea any more than Anne is, but she and Anne have taken on the task of keeping this idea alive for the benefit of the rest of us, and I respect that. Like I said, I remember SMF member Sistrum sharing this tip several years ago, but I wasn't interested in pursuing the idea at the time she mentioned it. (edit -- see later posts in this thread for the link to Sistrum's post)

Susie and all -- Just to be clear, I'm talking about bar soap; I apologize for not making that really clear in my first post. I debated whether this thread should be in the lye-based forum, but I put it in the liquid soap forum instead because I thought it would interest liquid soapers the most. LS dudes and dudettes have KOH on hand and know how to use it :) and bar soapers generally don't.

Marie -- I agree with Susie that you may want to look into adding a chelator to your soap. Two chelators are often mentioned here -- tetrasodium EDTA and sodium citrate. Both will reduce the chance of rancidity (DOS) in your soap and will reduce the amount of soap scum that forms when soap mixes with hard water.
 
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penelopejane

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It's an elegant solution to the problem, and I can't think of any other solution that really solves the problem of snotty castile except to make a bastille. And then it's not castile anymore.

An old-time Castile soap would have been made with a lye solution made from the ashes of seacoast plants. Because these plants had to deal with a lot of salt from the ocean, the lye solution had a lot of sodium in it, but there was still a goodly amount of potassium, since plants naturally contain potassium in their tissues. So the original castile would have been made with a mixture of sodium and potassium alkalis. Maybe this dual-lye recipe is taking castile back to its roots?

Thanks DeeAnna,
I add 1/2 tblsp ppo honey and 1 tsp salt to my Castile and it makes a difference to snott or its my water don't know.
This KOH idea sounds great I just have to work out where to buy it!
 

ngian

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After reading again this thread, I think it would be a more fair test to compare the 5% KOH's water solubility property between the exactly same oils. Olive oil is similar to Safflower HO but I think that they are not the same.

The above thoughts are based in my experiment I did with 6 soft oils at 40% in a recipe:

Testing a few soft oils in 40%

in which I felt that sunflower HO and Sweet Almond oils (which are similar to Olive oil) did lather a second or two faster than Olive oil and maybe I could see a few bigger bubbles with Almond oil vs Olive oil.

After seeing their FA profiles in soapcalc I guess that Olive's oil bigger amount of palmitic FA is responsible for that 1 or 2 seconds latency. I haven't worked with safflower HO but from its profile it looks like it is closer to Sunflower HO than to Olive oil.

Anyway by using 5% KOH in a NaOH bar will for sure add more solubility to the final soap, maybe similar to what sugar or Castor oil do (one of a forthcoming experiment).

DeeAnna your personal calculator computed 3% lye discount as 1,5% discount from NaOH and 1,5% discount from KOH and if so does this mean that it was finally used 3,5% KOH?
 
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