Feedback on soda ash/cocoa butter bloom and deionised water

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JuliaNegusuk

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Hi, I recently posted a thread about soaping in a heatwave and before that "cocoa butter bloom" in soap. In both threads we got talking about soda ash and whether that was the strange thing that was happening to my soap. I said I would try making without deionised water, as that was the only think I could identify as being different to other, ash free batches. Well I did and this is the result and I am as baffled as ever.

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The first pic are the worst, these are tea tree and mint, and lemongrass and poppy seed, and lavender and silk - though the latter aren't nearly as bad. The second pic are sandalwood and clay, with slight nibbles and issues on the white part of the soap but not the brown, and cinnamon, honey and oatmeal, and orange and patchouli, which are both absolutely fine. The other two soaps I made, my coffee, pumice and sea salt and rosemary and sea salt are also fine. All of these soaps have been made within days of each other, using the same technique and largely the same ingredients, apart from obviously different colourants and essential oils. They were all refrdgerated after pouring, I don't gel. I have always made my soap this way. They've been curing for about 3-4 weeks. They are made using a cellular silicone mould. I usually unmould within 24 hours, but this time waited for at least 48 hours before unmoulding. I also mixed at a slightly higher temperature than normal (about 120 degrees f instead of about 110 degrees f) in case that was a cause. They all came out of the mould looking perfect but developed the whitish look within a day or two of unmoulding. All of the problems are on the underside of the soaps not the tops. The tops of nearly all of them, even the worst ones, are fine. If it is soda ash, why is it only affecting the underside only? It isn't a surface issue, it penetrates into the soap. It literally looks like the corners and edges of the soap have been bleached. There is also some slight crumbliness in the whitish areas. For the past three batches (including this one) only the yellow, green and to a lesser extent, the pink soap and the white area of the sandalwood and clay soap have been affected, the latter not as badly this time. This is the side that is on the bottom of the cellular mould. In all cases the yellow and green soaps have been the worst. I use natural colourants - green tea wax mixed in the oils for the mint and tea tree, calendula petals mixed with the lye and left in for the lemongrass and poppy seed and madder root infused in the lye and sieved out for the lavender and silk. So all different colourants and made in different ways. All the ingredients are from reputable suppliers in the UK.

WHAT is going on!!!???!!! Help! It definitely doesn't seem to be anything to do with the water and I honestly can't think of anything else that I am doing differently from the test batches which were all fine. Except of course that now I want to sell them which I didn't when I was making the test batches. Do you think they know and don't want me too!?
 
The first two on the look like a partial gel with ash surrounding the ungelled portion. I have had it happen a few times. I also have found an ungelled soap can get chalky with heavy ash, that was during the days I did not gel soap. The pink one looks just like some spots of ash
 
The main source of ash is sodium carbonate that forms when excess NaOH reacts with carbon dioxide in the air. I don't know that anyone has the definitive answer on how to prevent this ash from forming, because I've never seen any solution that absolutely stops ash for all people all (or even most) of the time. If you absolutely can't stand any ash, it's time to develop techniques for removing it when it happens. Steaming and washing with water are two common methods of removing ash, as is planing thin shavings off the affected areas.

A couple of tidbits come to mind that might be useful to you --

Freshly made CP soap can be slightly more alkaline toward the bottom compared with the top. Since water (and lye solution) are denser than fat, the emulsion of lye solution and fat can vary slightly from the top of the mold to the bottom, even in a properly made soap. That's why you might see more ash on the bottom of a bar vs. the top.

Also, where the water evaporation out of the soap is highest, there is more likely to be ash, because the movement of water to the surface of the soap will also carry dissolved chemicals to the surface as well, including NaOH. And that's why you might see more ash at the edges and top of a bar. (And the edges also are where soap sometimes doesn't gel, even if it fully gels in the center, so Carolyn (cmzaha) may have a point there.)
 
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I’ve had this happen in cavity molds and I am not sure it’s soda ash which you can wash off. This stuff you can’t wash off. It’s hard and it’s inside the soap. It doesn’t really matter. I think it’s something to do with the batter cooling too quickly. The method I use also solves garden variety soda ash.

The way I solved it was to soap warm 115-120* F, spray the tops with isopropyl alcohol, have the mold in a cardboard or polystypere box so it can be covered. I actually put the mold in the box and pour the batter while it is in there so it doesn’t spill. Then I put a heated wheat bag in if it’s the polystyrene box or if it’s the cardboard box I wrap it in towels and put the heated wheat bag beside the box. Then I cover the lot (both methods) with a doubled over doona. I don’t touch it for 24-48 hours.

If you take them out of individual cavity molds too early the white stuff can develop later.

It is winter here now but I do the same in summer. In summer I don’t use wheatbags with my log molds but I do wrap them in the towels and doona. I only wait 18-24 hrs to cut log molds and they don’t get this white stuff.

My soaps are close to perfect now that I soap hotter and quicker (so the batter stays warm) and keep them warm until the salinity. Even my log Mold soaps. No spots or swirls or ash or hard bits. Thinking back I have had this with Castile in a log mold that I soaped cool. This confirms the theory I think.
 
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Thanks all. I am pretty sure its not gelled in the middle. And PJ is right, this wont just wash off. But the explanations make sense. What I cant get my head round is why only some of the soaps behave this way and why the same ones each time. I guess I will just have to stop being pigheaded and try cpoping or something and go for full gel and hope this cures it.

Thank you for your helpful comments.
 
My experience is the same as PJ's. My biggest heaviest ash was in individual molds. Not washable at all. Almost like concrete. I pretty much only use my log molds now. I pour, spray with 91% alcohol then put the lid on and cover with 2-3 towels. Leave it alone, no peeking (maybe ones or twice) to check for gel. Has eliminated ash for the most part. I have two that still get light ash these days, regardless of what I do, so I just embrace it.
 
My experience is the same as PJ's. My biggest heaviest ash was in individual molds. Not washable at all. Almost like concrete. I pretty much only use my log molds now. I pour, spray with 91% alcohol then put the lid on and cover with 2-3 towels. Leave it alone, no peeking (maybe ones or twice) to check for gel. Has eliminated ash for the most part. I have two that still get light ash these days, regardless of what I do, so I just embrace it.

If you peak I think you should spray with alcohol again.
Not sure why you check for gel? Isn’t it consistent for each recipe or does it change with the seasons?
Have you thought of making boxes with lids for the cavity molds and soaping hotter?
 
I have this problem with my soap made with neem and hemp seed oil. Refrigerated or not, I unmold and I get ash.... my soaps are smooth on top and bottom so I cover the ummolded soap tops with saran while they cure. I also cover the soap after pouring into the cavities - I have round pieces of craft foam that I place on top of each bar (these are in round flexible trays of cavities). When unmolded the bottoms rest on paper towels so not an issue. If I think I'm going to get ash on the tops of my soaps made in log molds I will cut into individual bars and then flip them over so that the bottoms are exposed to air and the tops rest on paper towels while curing. If I make a soap in a 3" pvc mold I will unmold and then wrap the uncut roll of soap in saran and let it cure a few more days before cutting into individual bars.
 
I have also experienced this- I call it "inside ash." I always thought it might be stearic spots? Or something to do with trace? I made this horrific batch recently....Poured at really light trace and CPOP'd it.
 

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If you peak I think you should spray with alcohol again.
Not sure why you check for gel? Isn’t it consistent for each recipe or does it change with the seasons?
Have you thought of making boxes with lids for the cavity molds and soaping hotter?

I always get full gel. But when using different additives sometimes things get a bit too hot. I don't need any more insulation that's for sure. I stack my molds on top of each other too so that helps with heat. I never spray again after peeking. I just lift the lid a bit. I have wooden lids so they maintain heat well.
 
I have also experienced this- I call it "inside ash." I always thought it might be stearic spots? Or something to do with trace? I made this horrific batch recently....Poured at really light trace and CPOP'd it.

I think that is a form of stearic spots. But I guess it could be this hard ash. I found soaping hotter will prevent it.

I always get full gel. But when using different additives sometimes things get a bit too hot. I don't need any more insulation that's for sure. I stack my molds on top of each other too so that helps with heat. I never spray again after peeking. I just lift the lid a bit. I have wooden lids so they maintain heat well.

Thank you. That's the difference between us/our recipes. I don't get overheating with any of my recipes. I always get full gel but I have to insulate and cover to achieve it. I am still at the stage of making one batch at a time so I don't stack molds.

I've been very impressed with silicone lined wooden molds and lids. So easy. I am going to make a wooden box for my cavity molds.
 
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Hi, back again. I decide to stop being obstinate and try cpoping or at least raising my soaping temperature. I made half a batch (four and a bit soaps) and sort of cpoped two and sort of insulated two and a bit. I read a bit on the internet first luckliy, and found an article by a nice lady called Aunty Clara, which warned me about silicon rash, which are pits on the soap surface if you cpop in silicon moulds. So I took ker advice and left the soap to harden for a couple of hours before putting it the oven which I heated to 80 degrees c before switching off and putting the soap in. I covered it with a sheet of baking parchment and left it for several hours before taking it out and leaving it on the work surface. The other two and a bit soaps I left on the side but after a while I dumped some tea towels and a fleece blanket on top. I left both for 48 hours before unmoulding. Now, several days later, neither show signs of ash. I'm actually not sure whether they gelled either, they look the same as my non gelled ones but whether they did or not the slight extra bit of heat meant I got no ash. I made another soap too which I just left on the side with no insulation which also didn't either partial gel or ash. So I wonder if all I actually need to do is just not refridgerate. I now recall that all my partial gel issues were with goats milk soap which is why I have always refridgerated. I have never tried not refridgerating non goats milk soap before. However it still doesn't explain why only some of the varieties got ash.

However, now feeling much happier and that I am getting on top this issue and that working out a fool proof, ash proof technique is within reach. Thank you for you patient help and advice (which I have finally taken).
 
Really glad you are getting to the bottom of your ash problem.

I never refrigerate GM soap. I treat them the same way I tread all my other soaps.

I think 80*C (175*F) for CPOP is too high. I and many others preheat the oven to 45*C (110*F) and turn the oven off then put the wrapped soap in the oven and leave it undisturbed for 12 - 18 hours.

I have new molds that don't fit in the oven now so I simulate the oven by using a wooden box around my silicone molds and covering them with 2 doonas and leaving for 12-18 hours. I have just got a lidded polystyrene box that I am using with a heated wheat bag which might mean I can do without the doonas!

I know you are experimenting but I think you should choose one method or the other. Taking it in and out of the oven and covering and not covering it seems to be very labour intensive and worrying and unnecessary.
 
Yes, I will try and drill down to a seamless easy way of doing things. 80degrees c is the lowest my oven will go but It wasn't on for long and I switched off before I put the soap in. Maybe ash free is a bit hopeful but I've been there before so I hope to visit that planet again.
 
Yes, I will try and drill down to a seamless easy way of doing things. 80degrees c is the lowest my oven will go but It wasn't on for long and I switched off before I put the soap in. Maybe ash free is a bit hopeful but I've been there before so I hope to visit that planet again.

What I do is turn the oven off then use a thermometer to find out what temp it is before I put the soap in. I know it is pedantic but if you have it too hot the soap can go rock hard or oil etc.
 
What I do is turn the oven off then use a thermometer to find out what temp it is before I put the soap in. I know it is pedantic but if you have it too hot the soap can go rock hard or oil etc.
Not at all. Ovens are notorious for inaccurate temperatures. It happens all the time that an oven will heat either higher or lower than the desired setting. There are professionals who go around re-calibrating ovens in restaurants for this very reason. So checking the temperature when you use it is really wise. I do the same thing as well.

My oven's lowest stated temperature setting is 150° F, but I turn it a tad below that setting to get a slightly lower temp and that works for me. But I always check both the oven thermometer and my IR thermometer before putting the soap inside because ovens also heat up hotter initially before 'dialing' back a bit.
 
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