Soda ash and fragrance

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Carly B

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Would certain fragrances or micas cause soda ash? I made two batches of soap in the past week---same formula, same mold, same process. Only thing that
changed were my fragrances and colors and the pull through piece. The first one got ash all around the outside, but the second batch had no ash at all.

The ashy one is using Nurture Soap's Champagne fragrance (it's FABULOUS) and the other is using Oregon Trail's Mardi Gras (a long time favorite).


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Would certain fragrances or micas cause soda ash?

No. Soda ash is created when Sodium Hydroxide comes into contact with Carbon Dioxide and it is really inconsistent because I have make two loaves of the exact same soap...same recipe, same colorant, same scent, same mold...poured within minutes of each other and sat side-by-side on the same shelf in the garage and one developed soda ash and the other didn't.

Sometimes spraying IPA helps, sometimes it doesn't. Sometimes it's occurs during saponification, sometimes it occurs after unmolding/the cut. Sometimes it's just a light dusting, sometimes it will devour your soap.
 
Thanks, TheGecko. I guess what puzzles me is why? We take care in soapmaking, measuring weights to the gram or ounce, using tables and programs to make sure we are doing the safe, correct thing. One would think that repeatable actions make repeatable results, but chaos ensues. :smallshrug:
 
I guess what puzzles me is why? We take care in soapmaking, measuring weights to the gram or ounce, using tables and programs to make sure we are doing the safe, correct thing. One would think that repeatable actions make repeatable results, but chaos ensues.

On an intellectual level I understand the "science" of soap making, but as a Christian and former Wiccan I accept that there are things that just can't be explained by science.

Take the process of "saponification":

"the name of the chemical reaction that produces soap. In the process, animal or vegetable fat is converted into soap (a fatty acid) and alcohol."

"a process that involves the conversion of fat, oil, or lipid, into soap and alcohol by the action of aqueous alkali. Soaps are salts of fatty acids, which in turn are carboxylic acids with long carbon chains. "

"a 'hydration reaction where free hydroxide breaks the ester bonds between the fatty acids and glycerol of a triglyceride, resulting in free fatty acids and glycerol,' which are each soluble in aqueous solutions. This process specifically involves the chemical degradation of lipids, which are not freely soluble in aqueous solutions. Heat-treated lipid residues are more difficult to remove than nonheat-treated residues due to polymerization."

The more I try to dig into it, the more I feel like Charlie Brown listening to adults talk: whah whah whah. So I call it 'magic', because you really can't control the science...too many variables.
 
I guess it's like bread baking. Hubby makes a pizza from scratch most Friday nights. Same flour, same water, etc. Hubby measures ingredients in grams, so the only variable is atmosphere and time. And the dough is different almost every time.

I'm glad soda ash isn't contingent on fragrance. The champagne fragrance is amazing. :)
 
I think fragrance could play a role avoiding soda ash if it accelerates or promotes gel phase, or quick saponification. I made two soaps the other day, one with strawberry fragrance and the other with coconut lime verbena fragrance. I could tell the strawberry was going through gel even when poured in individual cavity molds, it didn’t develop soda ash, while the coconut lime did, a lot. I didn’t cover any of them, and waited two days to unmold as I wanted to avoid soda ash on the sides. (they usually develop soda ash AFTER the 24 hour mark for me).
 
I think fragrance could play a role avoiding soda ash if it accelerates or promotes gel phase, or quick saponification. I made two soaps the other day, one with strawberry fragrance and the other with coconut lime verbena fragrance. I could tell the strawberry was going through gel even when poured in individual cavity molds, it didn’t develop soda ash, while the coconut lime did, a lot. I didn’t cover any of them, and waited two days to unmold as I wanted to avoid soda ash on the sides. (they usually develop soda ash AFTER the 24 hour mark for me).
Exactly what I was gonna say @glendam. If one soap gelled it would be less likely to get soda ash. Or they could have both not gelled, but one was slightly warmer than the other and that temperature might make a difference.
 
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I think fragrance could play a role avoiding soda ash if it accelerates or promotes gel phase, or quick saponification. I made two soaps the other day, one with strawberry fragrance and the other with coconut lime verbena fragrance. I could tell the strawberry was going through gel even when poured in individual cavity molds, it didn’t develop soda ash, while the coconut lime did, a lot. I didn’t cover any of them, and waited two days to unmold as I wanted to avoid soda ash on the sides. (they usually develop soda ash AFTER the 24 hour mark for me).
Do you use a heating pad (or anything else) for any amount of time to achieve gel with cavity molds?
 
@kaygrrl yes, I usually force gel with cavity molds. I put the mold on top of a heating pad, leave it on high for 5-7 hours (because I use a high water discount, which makes gel more difficult to achieve on its own). I also cover the soaps/cavity molds with Press n Seal, then a shoe box on top (and a blanket). And I resist the urge to peak or lift the Press n Seal for at least 48 hours, 72 to be safe.
 
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I' ve had various issues with soda ash, and have to say that whilst I agree it can be insanely random, I do tend to find particular colours and fragrances ash more than others, eg my lemongrass and poppyseed coloured with calendula petals and my tea tree and mint coloured with green tea wax are by far the worst offenders every time. I can't gel my soaps as it messes with the natural colours making them muddy.

However I discovered recently that water discounting does help a lot. I now soap with a 1.5/1 ratio of water to sodium hydroxide instead of 2/1. I have been much less troubled with soda ash even when I refrigerate my soaps.
 
I came back to this thread because I have to change my answer. I just made a 2 lb soap and it turned out I only had 1 Oz left of the FO I wanted to use. So I divided the batter in half and scented the other half with something else (strawberry kiwi from Lone Star candle). I used cavity molds and only the soaps with the floral fragrance (a very old Edens Garden Cybilla from BB) developed soda ash. Given than everything else was the same, I was inclined to think it was a matter of time until the remaining bars developed soda ash too, but after three days it hasn’t happened. The other half was (strawberry kiwi) had some vanilla stabilizer as well. Both fragrances accelerated as usual, but the floral Eden’s Garden bars were visibly solid sooner.
I had a 40% lye to water concentration and did not cover them, it is very humid here lately.
 

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