Glycerin Liquid Soap - Zappy after 24 hours

[K8E]

Hello! I've been reading so many great threads on here with tips on making glycerin liquid soap. I'm hoping the community can help me.

I am on my second attempt at the recipe Irish Lass shared in the 101 video. First attempt we just won't talk about....lol. Huge failure.

However, second attempt seems on track and my paste looks like vaseline (great start). I'm feeling good about this attempt, but, 23 hours later and the paste still zaps. The soap is not clear in the dilution test and is bright fuchsia with pheno drops. See the photos.

Question: How long should the soap take to saponify? Do I wait another 24 hours?

Or, am I lye heavy and need to neutralize/add more oil?

Here's my recipe and soapcalc ratios. I used 3.66 oz of water to dilute the lye, then added 7.31 oz of glycerine to the lye water. Brought it to a Elmers glue type trace, put the lid on and left it alone. I have tried zap testing at 4 hours, 18 hours and 23 hours. All zap.

Thank you!!
Katie

Recipe Name:

New Print Recipe

Total oil weight​ 16 oz​ Water as percent of oil weight​ 68.58 %​ Super Fat/Discount​ 0 %​ Lye Concentration​ 25.000 %​ Water : Lye Ratio​ 3.0000:1​

Sat : Unsat Ratio​ 32 : 68​ Iodine​ 66​ INS​ 142​ Fragrance Ratio​ 0​ Fragrance Weight​ 0.00 oz​

​	Pounds​	Ounces​	Grams​
Water​	0.686	10.97	311.09
Lye - KOH 90% pure​	0.229	3.66	103.70
Oils​	1.000	16.00	453.59
Fragrance​	0.000	0.00	0.00
Soap weight before CP cure or HP cook	1.914	30.63	868.38

#	√	Oil/Fat​	%​	Pounds​	Ounces​	Grams​
1​		Castor Oil​	10.00	0.100	1.60	45.36
2​		Coconut Oil, 76 deg​	25.00	0.250	4.00	113.40
3​		Olive Oil​	65.00	0.650	10.40	294.83
​		Totals	100.00	1.000	16.00	453.59

 

[DeeAnna]

If your KOH has a purity higher than the 90% you assumed, the soap would be lye heavy.

My KOH is around 95-96% purity so if I used that recipe, my soap would have 5-6% excess lye. That would definitely and permanently be zappy.

What info do you have about your KOH? Is it really in the 90% range per your supplier?

 

[K8E]

Thanks for the quick reply, DeeAnna! My KOH is from Essential Depot. I couldn't find anywhere on the bottle or on their website where they actually state the purity. On the MSDS it shows between 84% - 92% (if I am reading it correctly).

Component Percent [%]
Potassium hydroxide
84.0 - 92.0
Water
8.0 - 16.0

 

[DeeAnna]

For your recipe, I estimate about 1 gram of citric acid powder added to the entire batch of paste should reduce the excess lye by about 1%.

You could try adding some citric acid if you have any on hand and see if you can get that excess lye neutralized. Just remember a little bit of citric acid goes a long ways.

If you keep track of the amount of citric acid needed to neutralize the excess lye, that will give you a handle on about what the purity is for this batch of KOH.

 

[K8E]

Thanks so much, DeeAnna! You always have such great chemistry advice

The paste was a very thick taffy, so I slightly warmed it up and added 1.0 g of citric acid and tbsp of water then mashed it the best I could with a potato masher. Retested and it still had a little zap and the clarity test was clear but after adding pheno drops it was still bright fuchsia. I added another 0.5 g citric acid and another tbsp of water which wasn't enough to make it pliable so I added a 3rd tbsp.

Mashed it up and retested from several areas and NO zap! The clarity test was clear and after adding pheno it was still pink, but, it was noticeably lighter.

I used my brand new PH meter and its showing 10.52. Is that still an acceptable PH for liquid soap?

So, my best guess is that my KOH is around 91-92%. Would you agree?

 

[DeeAnna]

I'm glad my suggestion worked for you. It's always something of a guess when trying to troubleshoot someone else's problems from a distance.

Yes, I'd probably go with a little higher purity for the KOH -- 91% or 92% sounds good based on your experience with this batch. You might also include a small (1%?) superfat on top of that, unless you don't mind doing the occasional neutralization as you've done with this batch. Superfat isn't just about the idea of making soap milder; it's also about ensuring safety.

None of the numbers we use to calculate our recipes are perfectly accurate -- we calculate lye weight based on averaged saponification values for the fats, we make assumptions about lye purity, and we also make assumptions about how much (or if any) of the lye is consumed by any of the additives we use. A small amount of superfat ensures the soap isn't lye heavy should any of our guesses and assumptions happen to be a bit off.

***

Phenolphthalein should always show color in liquid soap if this pH indicator is used properly, even if the soap does not have excess lye. This indicator shows color (pink/fuchsia) from a pH of 8.2 up to a pH of about 13. It's colorless on either side of this pH range. Properly made soap, whether made with NaOH or KOH, should have a pH in the 9.5 to 11.5 range, give or take a bit, so phenolphthalein should blush when added to any soap solution.

I know people use phenolphthalein directly on bar (NaOH) soap or on a dab of KOH soap paste or in concentrated liquid (KOH) soap. If the indicator blushes color, they often then try to correlate the intensity of the color to the pH.

When using phenolphthalein with a concentrated soap like this, the indicator is being affected by the low water content and isn't going to work properly. The pH will appear to be lower in a concentrated solution, but that's not the true pH. The pH of that very same soap would go UP if the soap was properly diluted so the soap could fully ionize.

So the pH test, whether you use a meter, pH indicator, or pH test strips, is only accurate in dilute solutions, not concentrated solutions.

 

[MaureenW]

Hello, I am a Soapmaker from Canada and make Artisan Soap bars but recently starting making Castile Hand Soap using KOH.
I was measuring and weighing out my ingredients and had a ‘moment’ and accidentally added too much water so I stopped what I was doing, poured it into a bucket, set it aside and started again.
But… didn’t want to be wasteful so thought I’d try to blend it and processed it in my crockpot anyway and much to my surprise it turned out beautiful! It didn’t get thick at all while blending, I cooked it overnight and followed the same procedure anyway. I did a PH test and it’s bang on where it should be. Nice, foaming soap.. no different than my other finished product.
Any thoughts?

 

[DeeAnna]

...Any thoughts?

Sounds like you made soap and it turned out okay. Good for you! What are you concerned about -- what feedback are you looking for?

When asking for help, it's best if you share your recipe, ALL ingredients, ALL in weights. And share the method you used to make the soap.

Also, I'll mention "castile" means different things to different people, so you might want to simply list the fat(s) in the soap -- then you'll know people will definitely be on same page as you.

 

[K8E]

I'm glad my suggestion worked for you. It's always something of a guess when trying to troubleshoot someone else's problems from a distance.

Yes, I'd probably go with a little higher purity for the KOH -- 91% or 92% sounds good based on your experience with this batch. You might also include a small (1%?) superfat on top of that, unless you don't mind doing the occasional neutralization as you've done with this batch. Superfat isn't just about the idea of making soap milder; it's also about ensuring safety.

None of the numbers we use to calculate our recipes are perfectly accurate -- we calculate lye weight based on averaged saponification values for the fats, we make assumptions about lye purity, and we also make assumptions about how much (or if any) of the lye is consumed by any of the additives we use. A small amount of superfat ensures the soap isn't lye heavy should any of our guesses and assumptions happen to be a bit off.

***

Phenolphthalein should always show color in liquid soap if this pH indicator is used properly, even if the soap does not have excess lye. This indicator shows color (pink/fuchsia) from a pH of 8.2 up to a pH of about 13. It's colorless on either side of this pH range. Properly made soap, whether made with NaOH or KOH, should have a pH in the 9.5 to 11.5 range, give or take a bit, so phenolphthalein should blush when added to any soap solution.

I know people use phenolphthalein directly on bar (NaOH) soap or on a dab of KOH soap paste or in concentrated liquid (KOH) soap. If the indicator blushes color, they often then try to correlate the intensity of the color to the pH.

When using phenolphthalein with a concentrated soap like this, the indicator is being affected by the low water content and isn't going to work properly. The pH will appear to be lower in a concentrated solution, but that's not the true pH. The pH of that very same soap would go UP if the soap was properly diluted so the soap could fully ionize.

So the pH test, whether you use a meter, pH indicator, or pH test strips, is only accurate in dilute solutions, not concentrated solutions.

All great advice, thank you again!