Oven Rebatch (CP)

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I had a chance to find the relevant link from Soapy Stuff. It’s sodium citrate that acts as a chelator, not citric acid. When adding citric acid to a “fresh” soap recipe, it combines with NaOH to produce sodium citrate. I don’t see how that reaction could happen when re-batching saponified soap unless there is excess NaOH hanging around.
 
I had a chance to find the relevant link from Soapy Stuff. It’s sodium citrate that acts as a chelator, not citric acid. When adding citric acid to a “fresh” soap recipe, it combines with NaOH to produce sodium citrate. I don’t see how that reaction could happen when re-batching saponified soap unless there is excess NaOH hanging around.
It would happen, but not in the way you'd like. You are mixing a strong acid with a salt (composed of weaker acids: fatty acids). The sodium will form a salt with the citric acid, leaving free fatty acids.

I welcome corrections on the best way to characterize/describe this interaction.
 
I decided to rebatch some soap today. I was wondering if it would okay to add oxide colorants and found this tutorial on the Rustic Essentuals website where they added fragrance and micas to rebatch at the end. Unless someone pops in to stop me before I do it, I’m going to try the oxides and see what happens.

My grated soap, which is from a loaf made with 2 lbs of oils, has been in the oven at 225F for an hour and 20 minutes. The starting temp would have been in the high 60s. I added 2 tbs of distilled water. The soap is just getting to 125F. Is it fine to leave it going until it melts, as long as I’m careful not to burn it?
 
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My grated soap, which is from a loaf made with 2 lbs of oils, has been in the oven at 225F for an hour and 20 minutes. The starting temp would have been in the high 60s. I added 2 tbs of distilled water. The soap is just getting to 125F. Is it fine to leave it going until it melts, as long as I’m careful not to burn it?
Yes, I usually turn my oven up to 220º and just check on it. You might want a little more liquid especially if the soap shred are quite dry.
 
OMG, I just made the biggest mess ever trying to rebatch a loaf of soap. At this point I’m sure I should have added more liquid. When it had not melted completely after 2 hours, I got impatient. It was definitely a shove it/jam it into the mold kind of finish. The soap was only a week old but was made from a 37% lye concentration recipe. :confused:
 
Sorry, you should have added more liquid which can be done at any time. Usually, an oven rebatch will result in a molten lava-like texture that is easily pourable. :( Too much liquid is better than too little.
I’m sure it will be good for a laugh when I unmold it :p

ETA: it turned out fine. I posted it here.
 
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LOL, that's good! I'm melting in the oven right now. :)
I put milk in it so guessing it will turn brown. I also forgot the EO's for scent so decided to try for coffee on the rebatch. :)
We'll see how it turns out.

I rebatched 3 different soaps last week that I was not crazy about and turned it into 1 3 lb loaf and 6 soap balls, I did end up adding a bit of tea tree, cypress, and orange EO to the melted soap along with some kaolin clay and sodium lactate. The soap was harder than I expected it to be the following morning and I'm giving it away to some gym buds for them to try.
 
I rebatched 3 different soaps last week that I was not crazy about and turned it into 1 3 lb loaf and 6 soap balls, I did end up adding a bit of tea tree, cypress, and orange EO to the melted soap along with some kaolin clay and sodium lactate. The soap was harder than I expected it to be the following morning and I'm giving it away to some gym buds for them to try.

That's great to hear! Glad rebatching isn't all bad. :)

I only did about half the batch so far in rebatch ... I separated the colors since they didn't want to stay together anyway and remelted the lighter color. I added coffee grounds before I started melting and mixed it in with the grated soap. After melting I stirred in powdered coffee and unsweetened cocoa into a little distilled water and then stirred that into the melted soap. It didn't turn out too bad, but probably should have let it melt a bit more. Will give it to the kids. lol
 
That's great to hear! Glad rebatching isn't all bad. :)

I only did about half the batch so far in rebatch ... I separated the colors since they didn't want to stay together anyway and remelted the lighter color. I added coffee grounds before I started melting and mixed it in with the grated soap. After melting I stirred in powdered coffee and unsweetened cocoa into a little distilled water and then stirred that into the melted soap. It didn't turn out too bad, but probably should have let it melt a bit more. Will give it to the kids. lol

Have you tried the soap yet? I have made a few batches of HP with ground coffee and unsweetened cocoa. I like the look and the smell, but it's definitely a hand soap.
 
Sooo... I wanna try this rebatching with a couple soaps that seized and riced. All the post I’ve read press the soap onto a loaf mold. Is it workable enough to put into a individual square silicone mold? I just don’t want to wrestle with it to cut after. Maybe I should make dividers for my slab mold... I just dislike cutting soap sometimes!!! 😩😫😖
 
Sooo... I wanna try this rebatching with a couple soaps that seized and riced. All the post I’ve read press the soap onto a loaf mold. Is it workable enough to put into a individual square silicone mold? I just don’t want to wrestle with it to cut after. Maybe I should make dividers for my slab mold... I just dislike cutting soap sometimes!!! 😩😫😖
Good question! :thumbs:
For a small batch, I grate up the soap, sprinkle with a bit of water, and put it in a Pyrex cup in the Microwave at half-power for 45 seconds - 1 minute or so. Let sit for 5 minutes then knead and shape with gloved hands and press into a lightly greased individual mold -- 2 oz, 4 oz, or 5 oz. I wouldn't do more than 8 oz at a time. No loaf cutting required. It will take a bit of practice to get the soap malleable without drying out.

HTH and GOOD LUCK!
 
Can you use the oven rebatch method on lye heavy soap? I realized I missed an oil in a soap I did yesterday. (so disappointed as it has a nice swirl). Would I grate the soap and add the amount of missing oil to it and go from there?
 
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