Funny thing happened on the way to making Liquid Soap...

[KimW]

While diluting soap paste into liquid soap, it has a layer of soap on top that will not dissolve. I've had it heating for a total of 8 hours in a crockpot (4 the other day and four today). There is a thin layer of bubbles on top, but under that thin layer of bubbles there is a layer of white soap...goo...for lack of a better word. Except for the liquid under this layer which is obviously liquid soap and not water, it kind of looks like salted out soap just before it curdles, but I have not added any salt. I noticed nothing odd while making the paste. What could be the matter? I know it's weird to make liquid soap with just Corn Oil, but that's what I did, for no particular reason other than to see what happens. Maybe this is what happens? LOL Thanks in advance.

Recipe:
Liquid Required 3.49 oz 99.03 g
KOH Weight 3.49 oz 99.03 g at 90% Purity
Oil Weight (Corn Oil) 16 oz 453.59 g
Fragrance Oil Weight 0 oz 0 g
Superfat 1%
Lye Concentration 50%
Liquid : Lye Ratio 1:1

Citric Acid 0.16 ounce

 

[DeeAnna]

So I'm not quite sure about your question. Are you're asking why the white goo won't dilute? One common reason is it might not actually be soap. This goo could be a layer of fatty acids, and fatty acids don't mix with water.

You used citric acid AND a 1% superfat. Are you using the citric acid to make citrate for chelating? If so, did you calculate and add the extra KOH needed to neutralize the citric acid?

You also didn't say if you'd used any correction for the KOH purity being less than 100%.

If no correction for purity, a positive superfat, and using citric acid are probably the reasons why you've got that goo layer.

Another recent poster got into this problem recently. See Liquid Soap Colorant & Scent ? The first part won't be valid for your situation, but keep reading until you get into the middle of the thread.

Kind of unrelated, but I'm puzzled why you made liquid soap with a 50% lye concentration. IMO, it's less hassle to use 25% -- more water in other words.

 

[KimW]

Ah - Yes, that is indeed my question, DeeAnna, thank you.
I allowed the soap calc to adjust the lye amount for me to neutralize the citric acid. But, I did not double-check the soap calc. Checking it now, it looks to be off, but only by about .5g off, giving a KOH amount that is .5g too low.
So, reading #23 of the thread you referenced, you think the problem might be over-neutralized soap. Your description there does look like what I'm seeing. Thank you for the link! I will follow the instructions for testing to see if that is the case.

Given that the soap calc isn't that far off on adjusting the for the citric acid, how I would avoid this in the future?

Only reason for the high lye concentration is that I typically use low water when soaping liquid oils to speed up trace. Always up for improvement though! How is the hassle factor lowered with more water?

 

[DeeAnna]

"...how I would avoid this in the future? ..."

Figure out why you have the error.

You did adjust the KOH to neutralize the citric acid, so that checks out. You didn't address my question about whether you adjusted for the KOH purity. If your actual KOH purity is lower than what you claimed when you calculated the recipe, that might be the trouble spot.

More water => Easier to stir the soap paste. Easier to dilute.

 

[KimW]

Yes, you're right I neglected to address the question about KOH purity. dooooh. So sorry. I did not adjust for my KOH purity - didn't even think about it. I left it at the default of 90% as I always do, but then again I don't need to make liquid soap that often.

My bottle from Essential Depot doesn't say, but looking at the SDS online it states "84%-92%" Potassium hydroxide with the remaining % being water, and the COA says "90.2% wt". Looks like I have a gap in my knowledge. Which of these would be the actual "purity" of the product?
https://www.essentialdepot.com/msds/KOH_COA.jpghttps://www.essentialdepot.com/msds/KOH_SDS.pdf

 

[KimW]

BTW - I haven't done the add some grains of KOH to the goo test, but I scooped off that top goo layer and then picked some up into my hand. It's clingy like lotion, and not slippery like soap. I suspect the little lather I did get from said goo was from the small amount of soap bubbles floating on top. This is great fun, finding something new in an otherwise dull day!

 

[Zany_in_CO]

Liquid Required 3.49 oz 99.03 g
KOH Weight 3.49 oz 99.03 g at 90% Purity
Liquid : Lye Ratio 1:1

For LS the ratio of water to lye is 3:1. You have to type it in on SoapCalc. There are times you can use 2:1 but then you risk the chance of the batch bloating up and over the pot.

To not know this basic information, I'm thinking you might want to go back to square one. Hence, the following:

TIP: Make small 12-16 oz. batches at first until you get the hang of it. 12 oz. oils makes 16 oz. paste that you can then divide up into four 4-oz portions to experiment with.

Alaiyna B's Blogspot is a good place to learn the basics and you can go from there. Much has happened since that info was posted in 2011. Hence, there are about as many different ways to make LS as there are LS-ers! LOL, so it is easy to get confused by too much research. Here are a few links to posts you may find helpful.

DeeAnna's SOAPY STUFF Table of Contents. Scroll down to "LIQUID SOAP"/

FAVORITE METHOD FOR LS MAKING

ADVICE ON DILUTING LS

COLOR & FRAGRANCE FOR LS

WHAT TO EXPECT FROM VARIOUS OILS IN LS

ETA: Although tempting, don't throw this batch away. It isn't going to hurt if you set it aside and wait until you have a bit more knowledge and experience. Then you can go back and figure out what to do with it.

 

[KimW]

Thanks, Zany! I'll peruse those links, though I'm not aware of a water:lye ratio requirement, on a "soap" chemistry level that is, for making LS.

I don't need to make LS very often, but I have made more than a few batches of LS over the years. No worries - I was never going throw out this soap! Perish the thought! LOL It's perfectly fine except for, as I believe DeeAnna correctly diagnosed, some floating fatty acids caused by over-neutralized soap, which was probably caused by a low purity KOH, or an error in measuring on my part. Easily skimmed off and away.

 

[Zany_in_CO]

Thanks, Zany! I'll peruse those links, though I'm not aware of a water:lye ratio requirement, on a "soap" chemistry level that is, for making LS.

I know nothing about the "soap chemistry level" other than that saponification is a chemical process.
The way I came up with the 3:1 ratio was when I first started making LS in 2004. At that time, there was little information on the process. Making Natural LIQUID SOAPS: Herbal Shower Gels / Conditioning Shampoos / Moisturizing Hand Soaps by Catherine Failor (Paperback) got the ball rolling when she published that book in 1999. The Liquid Soapmakers Yahoo Group (now defunct) started in 2000. I joined the group in 2004 so most of what I know I learned from the "pioneers" of LS making -- more practical know how than scientific.

When I down-sized all of Failor's recipes, I noticed that the water:lye ratio was 3:1. I also noticed that the water:lye ratio in other recipes like the one I found on MMS was 2:1 and it worked! However, when I changed fatty acids but not the ratio, the batch would bloat up and over the container. I learned to be prepared to put the pot in the sink!

So if your water:lye ratio of 1:1 works for you, I see no reason for you to change that. As I am so fond of saying, there are as many different ways to make LS as there are LS-ers!

 

[KimW]

I made more LS to test a new recipe. 0% SF, default 90% KOH purity selected, because that's the purity supplier confirmed. The same thing happened.
I used @DeeAnna 's method here to confirm that it was a layer of fatty acid (Liquid Soap Colorant & Scent ?).
Rats! I'm guessing I should dispose of this KOH since it's obviously not right? I've had it over 60 days so I can't send it back. Booo-hoooo

Or, if I bought a hydrometer is anyone willing to teach me how to use it to determine the actual purity of this KOH? Sadness.

 

[DeeAnna]

I don't know that you need to discard the KOH ... just estimate what its purity is and adjust the recipe accordingly.

Regarding the batch you already made, you can add more KOH to the diluted soap to saponify the excess fats or fatty acids. I'm trying to think of a simple way for the average soap maker to do this with the least chance of overshooting the amount of KOH needed. Here are my latest thoughts about how to go about this --

Go to your original recipe and note the KOH weight for the recipe as you made it. Leave the recipe EXACTLY the same EXCEPT change the superfat by 1% either up or down -- doesn't matter which. Recalculate the recipe. Note the new KOH weight. Subtract the smaller KOH weight from the bigger KOH weight. Remember this number.

This number represents the approximate amount of KOH needed to reduce the superfat by 1% for the entire batch. I'm going to call this a "1% KOH weight" for lack of a better name.

If you only want to fix part of the batch, you'll need to reduce this "1% KOH weight" in proportion to the amount of soap you want to fix. So if you want to treat, say, about 1/4 of the batch, then divide the "1% KOH weight" by 4. This answer is the "1% KOH weight" for treating only 1/4 of the batch.​

If you have some idea of about how much extra superfat you want to get rid of, you can multiply this "1% KOH weight" by the percentage of excess superfat you want to remove and add that amount of KOH to start with. I might play it safe, however, and err on adding a little less.

In other words, if you think you have 3% excess superfat, don't add 3 X "1% KOH weight" all at once. Instead, add 2 X "1% KOH weight" for starters. After that, if more fat needs to be saponified, add a "1% KOH weight".​

If you don't have any idea of how much extra superfat needs to be removed, then I'd add just a "1% KOH weight" amount as many times as needed until little or no excess fat is floating on top of the soap. It might get a little tedious, but it will work.

You can add dry KOH directly to the soap OR you can dilute the KOH in an equal weight of water. Either way will work -- do what makes you most comfortable. Stir in well. Let the mixture sit for some hours to overnight.

If you record how many "1% KOH weights" you had to add to fix the soap, that will give you some idea of how to compensate for your lower KOH purity when you use this KOH in the future.

I hope this makes sense!

 

[KimW]

Yes! That makes total sense. Thank you so much. Now I'm excited.

 

[KimW]

hmmmm. My figures. 1.52g = "1% KOH Wt". I had to add 30.4g KOH to get rid of the fatty acid layer. 20 "1% KOH Wt", so then my KOH purity is 70%. Correct?

 

[Susie]

I don't know that you need to discard the KOH ... just estimate what its purity is and adjust the recipe accordingly.

Regarding the batch you already made, you can add more KOH to the diluted soap to saponify the excess fats or fatty acids. I'm trying to think of a simple way for the average soap maker to do this with the least chance of overshooting the amount of KOH needed. Here are my latest thoughts about how to go about this --

Go to your original recipe and note the KOH weight for the recipe as you made it. Leave the recipe EXACTLY the same EXCEPT change the superfat by 1% either up or down -- doesn't matter which. Recalculate the recipe. Note the new KOH weight. Subtract the smaller KOH weight from the bigger KOH weight. Remember this number.

This number represents the approximate amount of KOH needed to reduce the superfat by 1% for the entire batch. I'm going to call this a "1% KOH weight" for lack of a better name.

If you only want to fix part of the batch, you'll need to reduce this "1% KOH weight" in proportion to the amount of soap you want to fix. So if you want to treat, say, about 1/4 of the batch, then divide the "1% KOH weight" by 4. This answer is the "1% KOH weight" for treating only 1/4 of the batch.​

If you have some idea of about how much extra superfat you want to get rid of, you can multiply this "1% KOH weight" by the percentage of excess superfat you want to remove and add that amount of KOH to start with. I might play it safe, however, and err on adding a little less.

In other words, if you think you have 3% excess superfat, don't add 3 X "1% KOH weight" all at once. Instead, add 2 X "1% KOH weight" for starters. After that, if more fat needs to be saponified, add a "1% KOH weight".​

If you don't have any idea of how much extra superfat needs to be removed, then I'd add just a "1% KOH weight" amount as many times as needed until little or no excess fat is floating on top of the soap. It might get a little tedious, but it will work.

You can add dry KOH directly to the soap OR you can dilute the KOH in an equal weight of water. Either way will work -- do what makes you most comfortable. Stir in well. Let the mixture sit for some hours to overnight.

If you record how many "1% KOH weights" you had to add to fix the soap, that will give you some idea of how to compensate for your lower KOH purity when you use this KOH in the future.

I hope this makes sense!

That is the same method I use. I call it "add a little and wait". It works for my non-math brain.

 

[DeeAnna]

hmmmm. My figures. 1.52g = "1% KOH Wt". I had to add 30.4g KOH to get rid of the fatty acid layer. 20 "1% KOH Wt", so then my KOH purity is 70%. Correct?

If your original recipe was based on KOH with 100% purity, then, yes, that sounds about right. I didn't re-read the info you provided about your recipe, so I'm not sure what basis you used for the KOH purity.

 

[KimW]

If your original recipe was based on KOH with 100% purity, then, yes, that sounds about right. I didn't re-read the info you provided about your recipe, so I'm not sure what basis you used for the KOH purity.

Ah - I was wondering about that part of the math. I based original recipe on 90% purity.
Given beginning with 90% purity and needing to add 20% "KOH Wt", then my purity is 80%?

I was almost proud of myself, btw. Took a good look at the FA layer, approximated the volume, quite arbitrarily halved that number (because the layer wasn't 100% fatty acids), calculated 90% purity KOH needed for that amount of oils from my recipe, refused to get stuck on wondering about said 90% purity and my calculations, realized it was very close to 20% KOH Wt Units, and made a solution of KOH:water at 1:1 for 20% KOW Wt Units and added solution 10% 10g at a time. Viola!

 

[DeeAnna]

I think this kind of correction is always going to be an "eyeball it" type of thing. Based on your story (above), I'd say you have very well calibrated eyeballs. Yeah, I agree with your thinking that your KOH is in the 80% purity range.

Well done!

 

[Zany_in_CO]

I'd say you have very well calibrated eyeballs.

Haha. Well said!