Soap Growing & Cracks

[ResolvableOwl]

This batch was originally intended to be my trial give soapnuts in bar soap a chance. The soapnut soap (left) actually went fine, but my control soap (right) crazed out in a truly uncanny way:





I've put the mould aside, as a size comparison. The soapnut soap has shrunk a bit (like one would expect during 8 days of cure), but the water-based soap has expanded by a good amount, and is covered all over with a craquelée pattern. It feels like soda ash, but there is so much of it! The left soap caught some soda ash as I know it (on the upper side facing to the air during the two days it stayed in the mould), But whatever happened to the other is just immense.

Recipe: 23% mango butter, 17% palm oil, 39% HO sunflower, 21% HL sunflower, ROE.
36% lye (with 1.1% citric acid added), combined when all ingredients were slightly above room temperature.
The only difference between the recipes is that the lye in the soapnut soap was NaOH dissolved in soapnut tea (made with distilled water), and in the control soap it was pure distilled water.
I mixed the batter, either in a separate container (both went reasonably quick, medium trace took some three minutes of stirring with the spatula), and then poured into the moulds (PP plastic), and left for two days untouched. They felt reasonably firm for unmoulding, but PP isn't the most forgiving material to release young soap. So I then put them into the freezer for a few hours, and they unmoulded like a breeze afterwards.
This is how they look like, 6 days later.

Now I have a neat test soap, but no reason to trust my control bar .


ETA: I should probably cut the control bar into half and see like it's looking on the inside.

 

[Ladka]

What made you decide on the recipe? I've been given a bag of soapnuts and would love to use them in CP lye soap. The trouble is I don't use palm oil or mango butter and would prefer to use oils from my stock (tallow, lard, olive oil, HO sunflower oil, regular sunflower oil, coconut oil).

 

[ResolvableOwl]

(Tried to) cut the non-soapnut bar in half: it broke apart after cutting half through it. Looks as if it consisted of 100% soda ash. I could easily snap apart one of the halfs, and it has that crumbly, frothy texture all through. Feta cheese is a good comparison (just that it's porous, hence a fair bit lighter).
ETA: Hand wash test: terrible lather, chalky skin feel (think of castile soap), and wiping is intensely ropy (again, similar to castile slime). And I remembered that I did have similar oddities before … 20% Castor | CP±OP | 2% Vinegar … a soap that was growing with time, had crackles all over, hardly any lather, and chalky skin feel.

What made you decide on the recipe? I've been given a bag of soapnuts and would love to use them in CP lye soap. The trouble is I don't use palm oil or mango butter and would prefer to use oils from my stock (tallow, lard, olive oil, HO sunflower oil, regular sunflower oil, coconut oil).

The choice of oils was for using up some remains, hence the odd percentages (and this also means that currently I couldn't fully reproduce the recipe myself). Prerequisites were that the recipe wouldn't contain CO nor castor oil.
The mango butter is not the culprit.
You would get a very similar FA profile from blending equal parts of HO sunflower : beef tallow : pumpkin seed oil!

 

[Iluminameluna]

Could the tallow be the culprit? Your soap has an uncanny resemblance to mine! Except for the fact that my recipe is not the same as yours in the least. I make mine CP, and use pork lard. Recipe: Lard 50%, OO 30%, CO76F 15%, Castor oil 5%. SF 5%. I used individual molds, but it still took over a week to be able to unmold mine because each one felt as if I'd made the recipe out of plaster with too much water. Just terrible!
In my instance, I just left them alone after unmolding, and it's now been 6 months (recipe made this past Aug). The soaps lather with amazing bubbles, don't leave hands or skin dry, and though the glacee look doesn't disappear, the soap itself doesn't crumble. It breaks easily once it gets thin enough, oc, but those pieces still lather like champs!

 

[ResolvableOwl]

Could the tallow be the culprit?

No (there is no tallow in my recipe). You're right, it really looks like mine, but unlike mine, yours at least lathers well.

Do you have well-behaved soaps from this silicone mould, with which you can compare the size? Just looking at my above photo frightens me because SOAP IS GROWING.

 

[ScentimentallyYours]

Just looking at my above photo frightens me because SOAP IS GROWING.

Maybe it just wants to be a fizzy bath bomb?

 

[ResolvableOwl]

You think that's a joke? Hear me out, maybe there is a grain of truth in there. I wondered what the least common denominator of all my plaster soaps was … organic acids (citric acid, vinegar). In the non-soapnut bar in #1 it was citric acid (bath bombs, you say?), and I just discovered cracks in another bar with added citrate (left in this photo). Uh-oh?

Oh well, the bar on the right differs only in that it does not contain sorbitol (but still has citrate and identical oil blend). A few stearic spots, but nothing to panic about.

 

[ScentimentallyYours]

You think that's a joke? Hear me out, maybe there is a grain of truth in there.

Actually, I DID think there was a grain of truth in it. But you’re the one who knows chemistry, so I was hoping you would explain. Thank you!

Would it make a difference if you used sodium citrate instead of citric acid?

 

[ResolvableOwl]

Oh well, I'm FAR from an explanation for this phenomenon . Not even a working hypothesis … too many batches with citrate + sorbitol went just fine. My plaster soap has zero lather, unlike the one of @Iluminameluna …

 

[ScentimentallyYours]

My plaster soap has zero lather, unlike the one of @Iluminameluna …

If the bar has already fizzed like a bath bomb, would you still expect it to have a good lather? I wouldn’t. Can you reproduce the growing-chalk-bar-that-doesn’t-lather in a repeat batch? That sounds like a huge challenge, but it would be enlightening.

Perhaps the soap nut tea changed the entire balance of your recipe? https://www.rjpbcs.com/pdf/2012_3(1)/53.pdf.
“Chemical Composition
All parts of the Sapindustrifoliatus contain phenolic acids such as proto catechuic acid, cis -p- coumaric acid, p-hydrobenzoic acid and cinnamic acid [10].
The major constituents of the fruits are saponins (10%-11.5%), sugars (10%) and mucilage. The saponincan beextracted by simple chemical extraction method [11]. The seeds contain fatty acid. The fatty acids are ofarachidic, behenic, linoleic, oleic, palmitic, stearic,oleanolic acid, and sapindic acid. The seed contain trifolioside A, sapindiside C, D, E, glucopyranosides of stigmasterol, kaempferol, quercetin, B-sitosterol, hederagenin, protein, carbohydrate and starch [12]. The pericarp of the fruit containsgenins, methylhedragenate and methyl oleanolate[13].”

 

[ResolvableOwl]

Perhaps the soap nut tea changed the entire balance of your recipe?

I am playing with soapnuts exactly with the intention to change the balance of my recipe. But oh well, if the oddball only were the one with soapnuts! Then I could blame them… but that bar is just fine, it was only the control soap that crazed out.

Ad lather&chalk/plaster bar: Dunno. My 20% castor “chalk” soaps had zero lather, but then again, 20% castor for sure counts as an exotic composition that doesn't have to work well in the first place.
I just tested the soapnut-control-soap. 11 weeks into cure, it does lather indeed, if only as reluctantly as to expect from the not-so-bubbly oil blend. It reminds me a lot of castile soap: liquid-ish, translucent suds with medium-sized bubbles, slightly slimy bar, and the typical chalky cleanliness after rinsing off. And terrible longevity. One time usage ate up some third of the bar.

And well, it feels a bit like styrofoam, because it's too light for its size, and is warm to the touch (thermal insulation, porosity).

 

[Dan9250]

It would be interesting to know if the "chalk" soap has a pH shift towards neutral. Can you test the pH. Even a pH paper test could provide some information.

 

[szaza]

I had a similar experience on 2 occasions. First one was zany's no slime castile (100% oo version). Mainly the ungelled soaps got so much soda ash they started to look weird and crack (when cutting them open, you could see a small slither of actual soap inbetween the thick soda ash on all sides). They also lathered less than their gelled counterparts (which also got ashy, but less so).
A second time was while using a high butter soap (20% co, 30 cocoa butter iirc). This soap didn't really get ashy, but cracked in a way you sometimes see with soap that has been in use for a while (getting wet and drying, expanding and shrinking all the time) except they'd only been curing for a few weeks (or maybe even days, it's been a while).
Oh and now that I think of it, I also had a chalky feel with the white part of a soap colored with ammonia extracts. The white part had ammonia to make it similar to the rest of the soap, but somehow got a very different feel to it.

Hope this helps a little..

 

[Iluminameluna]

The soaps are stable in size, and are only getting milder. I gave my local clinic some of them to test drive and they've been well accepted. I included printed copies of the soap recipe with them, with notes, so they could see what the soaps were made of. So far, no one has mentioned blossoming soaps.

 

[Megan]

And I remembered that I did have similar oddities before … 20% Castor | CP±OP | 2% Vinegar … a soap that was growing with time, had crackles all over, hardly any lather, and chalky skin feel.

I had a similar experience with a vinegar soap once...but I can't remember the other additive...I think there were just too many salts in the bar overall.

https://www.soapmakingforum.com/threads/vinegar-and-citric-acid.78430/
Here it is, it was citric and vinegar...and the high solid oil soap had the issue, but the high liquid oil soap did not

 

[cmzaha]

I had a similar experience with a vinegar soap once...but I can't remember the other additive...I think there were just too many salts in the bar overall.

https://www.soapmakingforum.com/threads/vinegar-and-citric-acid.78430/
Here it is, it was citric and vinegar...and the high solid oil soap had the issue, but the high liquid oil soap did not

I soap with vinegar at 50-100% as my liquid in all my soap with absolutely none of these issues. My recipes are either high tallow/lard mix, high palm/shea or high palm/lard based. I started with using citric acid but changed to EDTA/Sodium Gluconate combination as my chelator since it works better for me than CA. I have done this for several years now. No plastic feeling, and no cracking with my soaps.