How is the Crystal Structure of Soap Affected by Rebatching?

[MissE]

One of the most important things I've learned on here is that solid soap needs time for three things to happen: saponification to take place, excess water to evaporate and soap to develop a crystal structure. My question is, when you interrupt this process to rebatch soap, how do these all get affected?

Well, I suppose after introducing more water into the soap during rebatch, you'll need even more time for the excess water to evaporate but that's about all I can figure out here.

I understand from all the sources I read that saponification will be at least 95% complete in the first 24 - 72 hours of making soap (ranges in opinion). So, anyway, let's imagine I rebatch soap within a day of making it, does heating soap up again help this process along any?

And, I'm most curious about this, does the crystal structure of the soap start again or continue to develop when you rebatch, or is it truncated, or what?

Thank you, anyone?

 

[The Efficacious Gentleman]

Just thinking out loud - you're breaking the soap down quite a bit, so the structure will still need a lot of time to reform

 

[jcandleattic]

I'm no scientist, but I would think it would have to completely start over, as you are completely breaking the structure of the soap and then rebuilding that structure when you rebatch.

 

[DeeAnna]

I agree with the others. You're not just heating the soap, you're also adding liquid and mechanically mixing it. That's going to set the "cure clock" pretty much back to zero.

 

[earlene]

I think how much of whatever thing happens (start over completely, re-organize and change paths, or whatnot) would depend on at least a couple of additional factors. For example, if you are introducing new soap to the mix, as in when you do a confetti soap. And how much, if any lye excess or how much, if any SF was in the old soap. And how the new additives interplay with the pre-existing conditions. So many variables could exist to alter the formation of new and changing crystalline structure, but I doubt it would be curtailed (as in truncated), more likely re-booted.

So does this lead to another question? Does a re-batch need to start the cure process all over again? If that is the next question, then for me, I would say probably it does. Absolutely when it is a method that introduces new soap in to the re-batch.

 

[lmosca]

MissE and earlene,
that is exactly what will happen. No matter how 'aged' is the soap that you are going to rebatch.
Temperatures and additional water will literally reset the more or less ordered structure of the soap to an almost amorphous mass.
From there onward, evaporation of the new water will have to take place, and further, the organization of the fatty acid salts into a more crystalline ordered structure, which is a far longer process.

 

[jcandleattic]

Does a re-batch need to start the cure process all over again?

Does it HAVE to start the cure over? I would think yes because the complete structure of the soap had changed, by adding either extra oils/liquid.

Of course I've never rebatched fully cured soaps though, so I don't have any actual hands on experience with that and would have to fully cure a rebatch anyway.

The more I think of it, the more that's a good question. If it was a fully cured soap, and you didn't have to add any extra liquid, ?? maybe not?

 

[MissE]

Yes, in deed, the next question would be how you then treat rebatched soap with regards to curing time. Also, when I think of how rebatched soap doesn't easily adhere but has to be forced together I have to wonder, does this affect the crystallization of the soap too?

Thanks, everyone, for weighing in.

 

[SunRiseArts]

I have done several rebatch. If you add too much water, yes it needs to cure for a long time. If you add just right, IMO in four weeks is good to go. But the longer, always the better.