Bubble-like structure in my potato soap

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Anstarx

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I read about using potato in soap in the forum the other day and decided to try it, figured it would be fun to make a shower soap, and I'm making mashed potato for dinner anyway.
After unmolding, I found odd bubble-like structure throughout the surface of my soap. I kinda feel like it's a half gel of sorts since my soap did heat up but can't be sure.
bubble 1.jpg

→top, bottom, and side. There also also small bubbles on the top, not sure what those are.
bubble 2.jpg

Cut slice. It's a bit hard to see but there still is a little of that bubble structure there

My recipe is:
CO 20% Palm 35% castor 5% OO 25% SAO 15%
Additives: sodium lactate, sugar syrup, clay and tumeric powder for color, rosemary and clary sage eo
lye: water: mashed potato = 1:1:1

The way I did it was to scoop out some of the mashed potato (added milk and butter, nothing else yet) and mixed it with my oil using my SB.
After mixing as much as I can there was still separation (just oil and potato, lye was not added yet). I figured it's normal because of the the moisture in potato. After adding the lye and blending the separated layer started to emulsify. It traced pretty fast and started to heat up, but I added the colorant and poured in time. Was going for a rusitc look anyways. The mold was very warm to the touch so I didn't CPOP.

Now 48 hours later I went to unmold and cut the soap and voila, bubbles! I took some scrap and washed my hand with it, just the usual uncured soap feeling, no lye burn or anything.I've had half gel and full gel before but never had bubbles like this. Could it be the starch's work, or something else's happening?
 

earlene

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The sides & bottom looks like silicone rash. Did you use a silicone lined mold that had ever been used for CPOP in the past? I have read that a silicone mold that produces this type of rash in CPOP will continue to do so in subsequent soaps. (link)
 

Anstarx

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The sides & bottom looks like silicone rash. Did you use a silicone lined mold that had ever been used for CPOP in the past? I have read that a silicone mold that produces this type of rash in CPOP will continue to do so in subsequent soaps. (link)
All my silicone liner never had silicone rash before, and I've been using them for a long time with frequent CPOP. My oven has a ferment function that allow me to set temp between 35-45c and my usual CPOP temp is 40c. Never had overheating problem too.
The sides of my soap (except for the textured top) are all smooth to the touch, too. Nothing uneven.
 

earlene

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My mistake, I thought I was looking at the bottom & sides of the soap that had been in contact with the mold.

In that case, I have no clue, other than air bubbles introduced into the batter, that later popped leaving holes. But if that were the case, I would expect them to be visible throughout the soap.
 

Anstarx

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My mistake, I thought I was looking at the bottom & sides of the soap that had been in contact with the mold.

In that case, I have no clue, other than air bubbles introduced into the batter, that later popped leaving holes. But if that were the case, I would expect them to be visible throughout the soap.
Still, thanks for the input ;) I will let it cure and test it then to see what happens. I guess it's just another one of those soaping mysteries.
 
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I have seen heavy condensation leave such a look on the outside. As for the inside, it looks like your soap went into a pretty hot gel which could account for the inside look. the condensation could have collected after your soap was cooling down. If my soaps went into a hot gel inside my HDPE molds the butcher paper could collect condensation which could build up in my crate and water spot the soap. This is why I always covered my crate with a towel before putting the lid on my crate to catch the condensation
 

Jibbian

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I've had something very similar (though less pronounced) happen to several batches of soap. I don't have a solution or an answer, but here's a link to my post with a similar issue. The gentleman who responded thought it had to do with clay; I see you added clay too. So maybe that's the culprit?
 
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