Soap expanded in the mold?!

[Guspuppy]

Back in January I made an unscented, uncolored, 60% olive oil soap. I just started using it a few days ago and LOVE IT. So, I made another batch yesterday. It was the exact same recipe as the previous batch, only I used some of the faux seawater from the ZNSC recipe, thinking the salt in the water would help it harden up for faster unmolding. This morning I went downstairs to unmold the soap and it had curiously swollen in the mold overnight! The sides were bowed out and the soap had pushed up above the mold edge. I wish I had thought to take pics before I removed it but no. Anyway it was hard enough to cut, so I did. The soap is so curious! Kind of like a crumbly hard cheese. And there is such a deep layer of ash on the top that it rolls up in little balls if I brush my finger over it. I tried to bevel the edges of one bar but it kind of crumbled into balls. I put it away to harden a bit more before beveling the rest but it's so weird I had to come and tell you all! I'll be interested to see what happens with cure!
*end piece shows the swelling. Also, I'm assuming that's ash but it is the exact same color as the soap so maybe it's soap?? Hard to tell with an uncolored bar!

 

[Todd Ziegler]

Your complete recipe would help us figure out what went wrong but I will give you a general answer.

Was your mold silicone and was it inside a wood box? Because soap can expand when it gets hot and if your mold sides are unsupported, then it will go sideways instead of up. My soap expands just a little, even though nothing in the recipe was wrong. Your faux saltwater good have been been the culprit but I'm sure someone else might have a better answer for you. However adding your recipe will help us tremendously.

 

[AliOop]

I agree with Todd that the soap probably just got warm and expanded the mold sideways a little, with some heat deformation on the top, as well. It definitely looks too soft to cut yet.

Let us know how it looks and behaves after a few more days. And knowing the full recipe would definitely help, too. For instance, if you used SL in addition to the faux seawater, that could make the soap crumbly. It is just hard to say without knowing more.

 

[Guspuppy]

It was just olive oil 60%, CO 30%, SAO 10%. The lye water ratio was soap calcs standard 38%. Nothing else. No additive. No color. No FO. I poured it in my 60° basement after SB to thick trace and put a cardboard box over it. No wood to insulate. I think it had to have been the faux seawater because I made this exact same recipe two months ago and it came out totally different.

It was weird, I thought it was too soft to cut too, due to the crumbly-ness of it, but the cut surfaces of the inside were much firmer than the top. The drag marks from the wire were from dragging down the ash or whatever was on top. I also have never ever had soap expand and bow out the sides of the mold.

 

[AliOop]

Not sure if you changed batch sizes, but if you did, using the default 38% water-as-percent-of-oils setting could account for the difference in results using the same recipe. That setting will cause very inconsistent results when you scale your batch size up or down. Your results will be more consistent over time if you use the water:lye ratio, or lye percentage setting.

Other than that, nothing jumps out at me from what you shared. Is it possible that there was a measuring error?

 

[Guspuppy]

Batch size was also the same. No measuring errors.
I normally use a 33% lye concentration as opposed to water-as-percent-of-oils, but for this soap (the original iteration) I was trying someone else's recipe so decided to follow it exactly. And I loved the results so much that I didn't want to change that this time just in case. The faux seawater was a spur of the moment decision though.
It's only a trial batch of 4 bars so no big loss if it doesn't work out. I was just so amazed by the swelling in the mold. Lol.

 

[Todd Ziegler]

The thing about making soap is that, even if you use the same recipe, you can still have a different result. However, I would not consider what happened to your soap, out of the ordinary.

What type of mold did you use?

 

[Guspuppy]

Silicone. The small, thick-walled 1-lb one sold by most of the soaping supply companies.