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Countryside

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I was wondering if anyone has made a soap with 90% NaOH and 10% KOH. I have made soap with 95% NaOH and 5% KOH. My soap is high in Oleic acid and that is why I chose to use this method. I am wondering if that 5% extra KOH would add any extra benefits. I realize that I may have to experiment on my own but any input would be great.
 

DeeAnna

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I use 5% KOH a lot, but haven't tried 10% KOH -- quite happy with 5% in my high lard soaps. I don't usually make soap high in oleic acid.

KOH increases the water solubility of soap and oleic acid soap is already highly soluble, so increasing the KOH is likely to result in an even more soluble soap and possibly one that is softer as well.

A former member Sistrum said "...I now add 10% of my NaOH to my batches high in lard and or tallow to help with lather, but will probably keep going higher just to see where I feel the cut off is for my formulas...."

Source: KOH and NaOH in shaving soap
 

Countryside

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Ok. Thanks so much. I also add vinegar to my batches. From my understanding this helps with the hardness of the bar. I do add the extra lye needed for the vinegar as well.
 

DeeAnna

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A caution -- perhaps you already realize this, but it's easy to think a soap that is physically hard is the same as a soap that has low water solubility. These two properties aren't necessarily the same. A high oleic soap that's hardened with vinegar will still be highly soluble in water.
 

Countryside

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Ok. I figured that but not sure as to what degree. According to the calculator I use, the oleic percentage is around 50%. Do you think that it’s reasonable to assume that the vinegar will have some affect on the solubility or does it only affect the physical hardness? I would prefer not to add more coconut oil to my recipe. It is currently around 20%. To my understanding this helps to make a hard, less soluble bar. I think I have read somewhere where babassu oil performs similar to coconut oil but it is not within my budget to put that into my soap. I also would not like to add palm or animal products.
 
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cmzaha

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Adding more CO, Babassu or PKO will make your bar harder but more soluble so it will not last as long. Higher Palmitic and Stearic will add longevity to your bar. I use 5% KOH in all my bars, with 50-100% Vinegar. I like vinegar as it helps with faster un-molding. My bars are hard enough so that is not my purpose of using vinegar. My go-to recipes one vegan one non-vegan are either high palm or high tallow/lard combination. Obviously I have no issues with using any of those fats and they make great soap. With 5% KOH, with 1.1% Sorbitol, 15-17% CO my soaps lather very well after a 2-month cure and fantastic after a 4-month cure.
 

Countryside

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Ok. I think I have been looking at it in the wrong prospective. I need my soap to be less soluble vs having a harder bar of soap.
 

Zany_in_CO

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You're welcome, Countryside.
I expect anyone who tries the recipe to put in their own "little tweaks". That's exactly what I would do! 😄 BUT! Before tweaking, I highly recommend making a small batch first paying close attention to the details. For example, I once subbed HO Sunflower Oil for part of the Olive Oil and the result was slimey mushy soap. ACK!

Just for curiosity's sake, might I ask what "little tweaks" you're thinking of? I might be able to save you some time, money and frustration if they aren't compatible with the intent of the formula, i.e., no slime, quick cure, long lasting, hard bar.
 

DeeAnna

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"...I am a little fearful of the 0% superfat ..."

Don't be. It's no cause for fear. Let me explain --

NaOH is not 100% pure, but most soap recipe calcs assume it is 100% pure.

The difference between the assumed 100% purity and the real purity of your NaOH (often in the mid 90 percents for most NaOH I know about) is what I call the "hidden superfat".

Real superfat = Desired superfat + (100 - Actual lye purity)​

If you enter 5% superfat as the desired superfat for a recipe and are using NaOH at, say, 96% purity, the real superfat % is --

5 + (100-96) = 5 + 4 = 9%​

This means a recipe at 0% desired superfat STILL has a 4% real superfat due to the purity difference.​

I routinely use 2-3% superfat and my personal recipe calc also corrects for the actual purity of the NaOH. In other words, my soap recipes don't have any "hidden" superfat.

So if I can make a soap with a 3% real superfat and have it turn out fine, you can make a 4% (or whatever your hidden superfat is) and have it be fine too.
 

Countryside

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I did not think about it that way. Thank you for that. I really appreciate it. I will do a little experimenting today.
 

Zany_in_CO

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In addition to what DeeAnna explained, the purpose of 0% SF is to saponify as much of the OO as possible to reduce slime. I would also recommend only 5% shea butter for that reason. You can tweak the amount in subsequent trial batches. The addition of shea butter lowers the "Condtioning" value, ups the "Creamy" lather value, and ups the "Hardness" value. But the differences are negligible, but likely noticeable, in my experience, when I add a bit of butter to my formulas.​
Caution: I use Pomace OO but I'm guessing you do not because few suppliers carry it. Most soapers use Grade A Refined OO or Pure OO because it is more readily available, i.e., Kirkland brand at Costco. Either of those are fine.​
EVOO (Extra Virgin) off the grocers shelf is NOT recommend for soap making. Of all the grades of OO it is the most likely to be adulterated, although it does happen to the other grades (ask me how I know! haha). Google "fake olive oil" for more information. That's not to say you can't use it, just a precaution if your olive oil doesn't perform as it should.​
Screen Shot Comparison: 100% OO​
100% Olive.png
Screen Shot Comparison: With 5% Shea Butter​
5% Shea 95% OO.png
 
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penelopejane

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Thanks so much for all the input. I use regular OO. No EVOO.
If you know your EVOO is not adulterated there is no reason not to use it it soap.
In Australia it is Good quality and fairly cheap and being the first cold pressed oil it is the most olivey oil you can buy.

if I won’t eat it (and I’m fussy, I know) I won’t put it in my soap. It’s the reason I make soaps - so I know exactly what went in it.
There are lots of different opinions out there about soap ingredients. I suggest trying different ingredients for yourself to get a personal opinion on what you can buy locally. It’s not just the ingredients that make a difference either. It’s your skin, your soaping environment, your climate and a whole lot of other factors that go into your particular soap.
 
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