What caused this texture (and how do I recreate it)??

[Maddiesiler]

Meet the “fat soap”.

The soap I almost scrapped because I hated how it looked and felt. But the soap that my mom is in LOVE with and desperately wants me to figure out how to recreate!

It has a very rough texture, but the spots fall off when you rub them. It’s like a natural exfoliant.

Here’s the basics of the Pumpkin Pie inspired “fat soap”:
Superfat: 5%
Lye concentration: 34%
Fats:
- 90% tallow
- 7% castor
- 3% coconut oil
Essential oils:
60% Orange
25% ginger
10% cinnamon
5% clove
Others:
Honey (2tsp/ppo)
Kaolin clay (1tsp/ppo)
Sodium gluconate (0.8% of batch weight)

Pumpkin purée subbed 1:1 for water. Lye was mixed with a small amount of water (about 25% of total liquid) Purée (remaining 75% of total liquid) was added at the trace.

Soaped with both temperatures in low 80°. Added honey/clay/essential oils/purée at trace

Put straight into the fridge!


This soap set up normally and cut clean at 24hrs. But within the first week after cutting they started to develop these lumps! It also took longer to cure than normal. I’ve made variations of this recipe a bunch of times, and they are all fully cured at about 5 weeks. This one took probably 8 - 12 weeks before it no longer ran white water.

Thank you all!

 

[TheUser]

Very interesting. I'd guess some water soluble ingredient was at a saturated suspension and when the water evaporated, it started percipitating. I'd guess the sugar from the honey or sodium gluconate.

 

[Maddiesiler]

Very interesting. I'd guess some water soluble ingredient was at a saturated suspension and when the water evaporated, it started percipitating. I'd guess the sugar from the honey or sodium gluconate.

So interesting!! Maybe the combo of the honey, sodium gluconate, and pumpkin just was too much sugar? I might try to repeat the recipe exactly as is and see!

 

[ScentimentallyYours]

Pumpkin purée subbed 1:1 for water. Lye was mixed with a small amount of water (about 25% of total liquid) Purée (remaining 75% of total liquid) was added at the trace.

Are you certain the lye was fully dissolved @Maddiesiler? My first thought was that the spots could be stearic spots caused by the oils not being warm enough. But then I read the recipe. Lye spots will be hard.

Was your lye in the bead form, or the flake form? What was the weight of your lye in the recipe? What was the weight of the water? Lye needs an equal amount of water weight to fully dissolve, 50:50.

You mentioned you did not like the feel of the soap. Do you think the soap part without the beads is super fatted? I.e. did it have enough sodium hydroxide to fully saponify? Please check the weight of lye and water and let us know. Your soap may not be safe.

Edit to add: I have never seen sugar cause white spots. If it’s not lye, they could be stearic spots caused by soaping at too low a temperature for the tallow.

 

[AliOop]

Are you certain the lye was fully dissolved @Maddiesiler? My first thought was that the spots could be stearic spots caused by the oils not being warm enough. But then I read the recipe. Lye spots will be hard.

Was your lye in the bead form, or the flake form? What was the weight of your lye in the recipe? What was the weight of the water? Lye needs an equal amount of water weight to fully dissolve, 50:50.

You mentioned you did not like the feel of the soap. Do you think the soap part without the beads is super fatted? I.e. did it have enough sodium hydroxide to fully saponify? Please check the weight of lye and water and let us know. Your soap may not be safe.

I agree. It sounds from her description that she did not dissolve the lye in an equal amount (by weight) of water. If those are undissolved lye crystals, that soap could cause serious skin damage, especially to mucous membranes.

 

[Maddiesiler]

I agree. It sounds from her description that she did not dissolve the lye in an equal amount (by weight) of water. If those are undissolved lye crystals, that soap could cause serious skin damage, especially to mucous membranes.

Totally possible! The only thing is though... I've been through five bars and it feels great super nice lather and not a bit of irritation! I used a bit of water, but this was my first time with pumpkin. I subbed it 1:1 for the remaining amount of liquid. My lye was 4.08oz and my liquid was 7.92oz (5oz pumpkin and 2.92oz).

 

[Ford]

Hi,
you used 25% (2.92oz water) of your lye liquid. To mix with 100% (4.08oz) of lye? So, your initial lye solution would be heavy to start. Not sure if adding the remaining 75% liquid. After trace. Would delute the excess lye, to a safe level.
The spots/bumps look crystaline. Something is perspiring and crystallized. With the air. You say they was off? And there is no irritation?
Gelled vs non gelled would effect cure time. Good luck

 

[AliOop]

My lye was 4.08oz and my liquid was 7.92oz (5oz pumpkin and 2.92oz).

Thank you for clarifying that. What's still not clear to me is whether you mixed the pumpkin in with the water and lye. If you dumped the half-dissolved lye + water directly into the rest of the soap batter, then as @Ford said above, you run the risk that the undissolved lye particles will not come into contact with enough water to actually dissolve.

To say it another way, you must completely dissolve the lye in liquid, before adding it to the oils. If that's not what you did, then you are taking a big risk to use the soap. The picture you show, and the descriptions you give, sound very much like undissolved lye to me. Just because there hasn't been skin irritation yet, doesn't mean that there won't be irritation in the future. If any undissolved lye particle were to splash in someone's eye, they could be blinded. Is that risk really worth taking?