Grey blotches on charcoal soap

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brooklynmaker

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I use the same base mix for three different cold process soaps. For some reason the charcoal one has a recurring problem of coming out with what I can only describe as gray blotches. I use a custom silicon mold for my soaps so this makes it harder to insulate.
It looks like soda ash, but it's more pronounced because the soap is black. The odd thing is that it isn't on all of the bars either and it doesn't happen every batch! I have tried different temperatures. I have tried spritzing with alcohol. I don't know what else to try! I can try to steam them after but that is really laborious! Also, do you wait until they are cured to steam them? If a picture would be helpful I can post so you can diagnose. Thank you!
 
Yes, please-- a picture would be helpful
IMG-6859.jpg
 
It is a reaction between the soap ingredients and the mold components. I have one silicone mold that regularly creates a rash on the sides of the soaps - slightly different color and texture. But it only does that for certain recipes, and not others.

Are you able to wash off the grey stuff?
 
It is a reaction between the soap ingredients and the mold components. I have one silicone mold that regularly creates a rash on the sides of the soaps - slightly different color and texture. But it only does that for certain recipes, and not others.

Are you able to wash off the grey stuff?
Do you normally steam / wash off soda ash right after you unmold? I have tried to steam right away and i feel like it gets really messy.
 
I always wait till it is fully cured before steaming. It's less likely to recur that way. But I thought you might want to try right now, just to see if it does come off, in which case, you will know that it is ash. :)
 
I use the same base mix for three different cold process soaps. For some reason the charcoal one has a recurring problem of coming out with what I can only describe as gray blotches. I use a custom silicon mold for my soaps so this makes it harder to insulate.
It looks like soda ash, but it's more pronounced because the soap is black. The odd thing is that it isn't on all of the bars either and it doesn't happen every batch! I have tried different temperatures. I have tried spritzing with alcohol. I don't know what else to try! I can try to steam them after but that is really laborious! Also, do you wait until they are cured to steam them? If a picture would be helpful I can post so you can diagnose. Thank you!
Three things I have found that help with ash. 1- Lower your water, 2- Pour at a thicker trace 3- Cover your soap until it has fully saponified - up to 48 hours.
 
It kind of looks what has happened for me with two different soaps that used activated charcoal. I'm not convinced mine was ash, because it went through (not just the top). Didn't happen with other colors, or in bars where I used iron oxide for black. I decided it's something with activated charcoal specifically.
 
Three things I have found that help with ash. 1- Lower your water, 2- Pour at a thicker trace 3- Cover your soap until it has fully saponified - up to 48 hours.
Some folks also find that forcing gel and spraying the top with rubbing alcohol eliminate or reduce ash for them, as well. Gelling via insulating helps for me, but both CPOP and spraying RA on my soap results in a weird texture on the top, with no reduction in ash at all.
 
It kind of looks what has happened for me with two different soaps that used activated charcoal. I'm not convinced mine was ash, because it went through (not just the top). Didn't happen with other colors, or in bars where I used iron oxide for black. I decided it's something with activated charcoal specifically.
Yes, I feel like it's an activated charcoal issue. I use the same base for all other soaps and they do not have this problem. Maybe I should mix with iron oxide to reduce the charcoal.
 
I had a lot of ash on a charcoal soap once, and it looked a lot like that. Did you try steaming it off yet? If not, maybe try with just one bar so you know if that's what it is.
I have tried steaming if off and it does steam off pretty nicely when it's just surface ash. But other bars seem to have it ggo much deeper, like if you cut the bar in half, the middle is also grey. I don't understand!
 
Three things I have found that help with ash. 1- Lower your water, 2- Pour at a thicker trace 3- Cover your soap until it has fully saponified - up to 48 hours.
I use a water reduction. I can't pour at too thick of a trace because i'm pouring 100 individual molds at at time. Spraying with alcohol and covering doesn't always work for me.
 
Try what linne suggested above >>1- Lower your water, 2- Pour at a thicker trace 3- Cover your soap until it has fully saponified - up to 48 hours.

What I do is pour 400g or so into a spouted jug and SB that to medium trace and pour it into the cavity then add another lot of batter from the original jug and SB it to medium trace and pour it into the cavity mold. You have to try and accurately judge the right amount for 4 cavities at a time. Don't pour 1/2 a cavity. It is best to add the new mix to a bit of the SB'd left over and SB it all together.
My molds go into a wooden mold with a lid. When it is set I put plastic wrap on top to prevent air getting to it. Then put the wooden lid back on top.
I find I have less problems with that than Isopropyl alcohol but you can try that if you don't want to use plastic. Leave them in the molds for a few days. If you can't do that(need the mold to reuse) unmold them and cover them with plastic on a tray for a few days. Aim - keep the air away from them until they've cured for at least a week.
 
I have tried steaming if off and it does steam off pretty nicely when it's just surface ash. But other bars seem to have it ggo much deeper, like if you cut the bar in half, the middle is also grey. I don't understand!
That is exactly what happened with me and it drove me nuts trying to figure out. I think part of the problem is that what some people call "ash" isn't really soda ash but some other weird soap crystallization thing that no one fully understands. It's maddening.

I just don't use AC anymore. 🤣
 

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