How to achieve certain opacity/finish

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rainycityjen

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My latest few batches of CP have been crumbly in the corners with a tendency to flake when cut by wire, and have all had a pretty dull/powdery finish. They aren't lye heavy, and are otherwise fine soaps. I'm using a pretty standard 30/30/30 type recipe with 36% water and 6% Sf, so my prime suspect is the palm oil - it's a newer bucket from BB and seemed very solid and crumbly. (I melted and blended before using to try and mitigate stearic spots.)

I think soaps are most attractive when they "glow" a little around the edges in sunlight and have a smooth, slightly eggshell finish. What kind of recipe would achieve that? Planing and dunking in water only does so much. Ideally I need to keep using up this palm since I have so much of it.
 
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Are your soaps gelled? I would expect to that sort of glow from from your recipe if it gelled.
Any td or colorants to interfere with that glow? Discoloring fo's?
 
I don't gel, primarily I like to soap very cool to test fragrance, so they tend to not gel anyway. Last two batches used partial mica colorant, one FO discolored and one did not. Seems to be across the last few batches using the same basic recipe.
 
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Gelling makes the most difference there. 100% CO soaps are more translucent than many other soaps but I suspect the 20% SF is part of that equation, so increasing SF a touch may help, say from 6% to 8-9%. I have heard about extended gelling being helpful and I've tried that. I kept the soap is a strong gel for 3 hours before letting it cool down. I used my normal recipe and I don't know what exactly happens from extended gelling but the lather on those bars was far below par. Maybe the heat for that long affects how the soap organizes itself over time but while those were bars that were a bit more translucent, I wouldn't even give them away because the lather was so bad.

Using any opaque colorants like TD or mica would make it less translucent and clear colors, like lab colors or pigments will allow more light through.

Nothing scientific here but I've thought that soaps made with tallow or lard or OO were more translucent than palm. Maybe doing a test batch with 10 percent of the palm going to OO or one of your other oils would make a difference. Again, I have nothing to back me up on that idea.

Hope that's helpful.
 
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Just thinking out loud here --

I sometimes see this powdery slightly crumbly opaque look in soap that doesn't warm up much during saponification for whatever reason. You're right -- they're zap free and seem fine, but there's this odd texture thing that I don't like.

I can't absolutely say I know there's a connection, but I have wondered if a high-lard soap + cool saponification is causing this appearance issue. You mention you think your new palm may be the culprit -- it has high palmitic and stearic acids similar to lard, so this fits in with my vague ideas. Again, I'm not sure, but I wonder.

Anyways, so my suggestion next time you make soap is to make sure your soap stays warm while saponifying. Insulate the mold a little better or put the soap into a prewarmed oven and immediately turn the oven off (a low-key version of CPOP), or something like that. See if that helps.

And if you're open to an experiment with some of the powdery-crumbly-opaque soap you've already made, try this -- Warm the oven to about 170 deg F. Put your soap back into its mold, even if it's already been cut into bars. You don't need to put the whole batch in the mold -- just try a few bars so you aren't risking a lot if things don't turn out well. Pop the soap into the oven for about an hour or so -- long enough to warm through. Pull the soap out of the mold and let it cool.

See if that changes the appearance and texture to the firm, waxy, translucent look that you (and I) like. I've tried this twice now and what I've seen with my soap is it doesn't go into gel -- it doesn't get soft and vaseline-y. The bars stay completely intact as if the soap hadn't been heated at all. But this "after the fact CPOP" method seems to alter the structure of the soap slightly just as if it did gel. No guarantees on this, but it might be worth a try with a few bars and see what you think.

Hope this helps!
 
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Gelling makes the most difference there. 100% CO soaps are more translucent than many other soaps but I suspect the 20% SF is part of that equation, so increasing SF a touch may help, say from 6% to 8-9%. I have heard about extended gelling being helpful and I've tried that. I kept the soap is a strong gel for 3 hours before letting it cool down. I used my normal recipe and I don't know what exactly happens from extended gelling but the lather on those bars was far below par. Maybe the heat for that long affects how the soap organizes itself over time but while those were bars that were a bit more translucent, I wouldn't even give them away because the lather was so bad.

Using any opaque colorants like TD or mica would make it less translucent and clear colors, like lab colors or pigments will allow more light through.

Nothing scientific here but I've thought that soaps made with tallow or lard or OO were more translucent than palm. Maybe doing a test batch with 10 percent of the palm going to OO or one of your other oils would make a difference. Again, I have nothing to back me up on that idea.

Hope that's helpful.

Oooh this is interesting because I don't deal with gelled soaps often.

Why didn't your 3 hour gelled soap lather as well? (I mean -beyond the general acceptance that ungelled soaps tend to be more soluble than gelled) Do you think there's more to it?

I would say that a 40% palm with olive, co ,castor, gelled, is more translucent than a 65% lard, with co, safflower, castor, gelled. I have both sitting in my shower right now.

I also have a bastille, 80% oo, 15%co, 5 castor, and I think it's the least translucent. Wait...that may not count because I doubt that one gelled. In fact, I'm sure of it because there's a light powder ash on top.
 
And if you're open to an experiment with some of the powdery-crumbly-opaque soap you've already made, try this -- Warm the oven to about 170 deg F. Put your soap back into its mold, even if it's already been cut into bars. You don't need to put the whole batch in the mold -- just try a few bars so you aren't risking a lot if things don't turn out well. Pop the soap into the oven for about an hour or so -- long enough to warm through. Pull the soap out of the mold and let it cool.

Verrrry interesting. I will try this and report back.
 
I would think with proper cure, an ungelled soap would have the same solubility as a gelled one. Have you read that as a generally accepted idea or did you read something from Dr. Dunn or a study or such? I'm trying to think why gel would change that, again, assuming a proper cure time for each. I haven't really paid attention to how long one lasts in the shower over the other, to be honest.

I have been wondering why the extended gel changed the lather so much but I don't know. I went back and tried that soap a number of times. After a couple months, I could get a bit of lather from it but for the first number of weeks, there was just nothing and my regular recipe is formulated to (at least try) to explode with lather. It does a pretty good job generally so this was very unusual. The only thing I can think of is that the extended period of time allowed or caused some organization within the soap that is not lather-friendly. Since that part is an integral experience of using a soap, I didn't try the experiment again, although I should, to see if the same happens.

I would love to see some pics of your different bars with the same lighting around or behind them. Sometimes I am looking for more translucency to make an effect pop or for a certain look and perhaps I've been going the wrong direction. I do think the higher SF adds to translucency; that part I feel pretty confident in because of the Superfat Swap we did some time ago with SF's ranging from negative 3 to 28% or so. However, if you have bars at the ready to compare, I would be very interested to have a look.
 
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Another thought.. My soaps turn out crumbly around the edges when I pour the batter too thin. I've noticed pouring at a more pudding-like consistency makes the texture of the finished soaps so much nicer.
 
Yes, I fully agree with that. Getting batter to definitive trace make the texture of soap much nicer. Pouring too thin gives it an odd look, although I would say that if you pour just past emulsion, you will get more translucent soap but with poor texture. And trying to gel a soap poured very thin is tricky because it's more likely to separate.

I wonder if it would be more translucent if your poured very thin- at emulsion but did not gel. Then at the 24-48 hour mark, if you put it back in the mold and heated it in the over, would the translucency change? DeeAnna mentioned that the texture will change and become nicer but how would a bar done that way compare in translucency to a bar SB'ed to medium trace and gelled? These and other burning questions....
 
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Yes, I fully agree with that. Getting batter to definitive trace make the texture of soap much nicer. Pouring too thin gives it an odd look, although I would say that if you pour just past emulsion, you will get more translucent soap but with poor texture. And trying to gel a soap poured very thin is tricky because it's more likely to separate.

I wonder if it would be more translucent if your poured very thin- at emulsion but did not gel. Then at the 24-48 hour mark, if you put it back in the mold and heat it in the over, will the translucency change? DeeAnna mentioned that the texture will change and become nicer but how would a bar done that way compare in translucency to a bar SB'ed to medium trace and gelled? These and other burning questions....

It's starting to look like I have a whole suite of soapy experiments queuing up... :)
 
Yes, I fully agree with that. Getting batter to definitive trace make the texture of soap much nicer. Pouring too thin gives it an odd look, although I would say that if you pour just past emulsion, you will get more translucent soap but with poor texture. And trying to gel a soap poured very thin is tricky because it's more likely to separate.[/QUOTE

.................what? How could I have never noticed this?

Okay, now that has really got me very curious! I've done tons of plain uncolored unscented lard soap (give to Lost Boys) and I've poured at all different kinds trace. Most are very thick simply because I love the freedom of working with rich thick batter without worrying about swirls. I've never noticed a difference in translucency or texture - but I've also never looked for it.
 
It has to be very very thin, like just barely at emulsion, to get the more transparent look. I've done it accidentally and then fretted for a long time about if it's going to hold together, and usually there is a little oil on top so it's threatening to separate. If you SB to any sort of trace, this doesn't happen. I would have to go see if I have any bars like this hiding in the basement. I generally consider them busts because micas don't look right in them- the colors are poor and poorly defined, the texture is odd and they don't lather up as well as soap taken to trace.
 
Ungelled soap being more soluble than gelled? That idea came from the forums when I was just starting out. Gelled soaps were "harder" than ungelled so lather was slightly less. Don't remember reading about it in Dunn's book.

As for the extended gel affecting the soap - gel is like cooking - and heat changes things. So...structure of chemical bonds? Do some of the oils become "denatured" like proteins? Are the molecules different sizes? Who knows what the possibilities are.

Let me see what I have left for unscented soaps. Just bought a new phone with a much better camera so comparing images just might work.
 
I thought I'd post a few pics of a 100% CO with 20% SF soap. It's not as thick as my normal bars because I was using it for an embed but I did my best to show the translucency. It is colored with mica and has TD lines in it so uncolored, it might allow a bit more light through.

Okay maybe not the best pics. I'll try again tomorrow.

Screen Shot 2016-03-10 at 12.10.47 AM.jpg


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Screen Shot 2016-03-10 at 12.11.03 AM.jpg
 
Yes, I fully agree with that. Getting batter to definitive trace make the texture of soap much nicer. Pouring too thin gives it an odd look, although I would say that if you pour just past emulsion, you will get more translucent soap but with poor texture. And trying to gel a soap poured very thin is tricky because it's more likely to separate.

I wonder if it would be more translucent if your poured very thin- at emulsion but did not gel. Then at the 24-48 hour mark, if you put it back in the mold and heated it in the over, would the translucency change? DeeAnna mentioned that the texture will change and become nicer but how would a bar done that way compare in translucency to a bar SB'ed to medium trace and gelled? These and other burning questions....


I don't know if it will be more translucent but I do know that pouring very thin, not gelling and then putting it in the oven does work well.

I did it with my GM Castile soap for the (February) challenge that had a steep water discount. I put it in the fridge overnight so it wouldn't overheat and in the morning it was still soooooo soft (like a thick trace!) that I decided to pop it into a pre warmed oven at 170 and shut it off. I kept it there all day. I think I turned the oven on one more time somewhere in the mix.

My soap didn't go brown or discolor from the GM but my soap still firmed up much faster than it would've had I not placed it in the oven. It still had a chalky feel to it so I'm not even sure it gelled or not! But the heat did help with unmolding. I don't know how it affected translucency since I wasn't paying attention to that. All of my bars are typically very opaque though.
 
Ungelled soap being more soluble than gelled? That idea came from the forums when I was just starting out. Gelled soaps were "harder" than ungelled so lather was slightly less. Don't remember reading about it in Dunn's book.

As for the extended gel affecting the soap - gel is like cooking - and heat changes things. So...structure of chemical bonds? Do some of the oils become "denatured" like proteins? Are the molecules different sizes? Who knows what the possibilities are.

There is actually a photo in the book showing how much more an ungelled soap expanded from absorbing water than a gelled soap did.

Like solid oil, soap apparently has different crystal polymorphs -- certain defined, characteristic shapes and sizes that the soap crystals can take. Certain crystal organizations can predominate depending on the composition of the soap, moisture content and the conditions under which it solidifies (if it was in gel phase). I think this probably accounts for the variations in hardness, lather, and appearance.

Gel phase is called neat soap, which is the liquid crystal form it takes when it melts. At that point the crystals can slither around. The soap will definitely reorganize itself at the crystal level if it melts and re-solidifies.

If you use solvents so the soap solidifies into a microcrystalline form -- crystals so small that it's practically homogeneous, you can end up with soap that's transparent.
 
I did it with my GM Castile soap for the (February) challenge that had a steep water discount. I put it in the fridge overnight so it wouldn't overheat and in the morning it was still soooooo soft (like a thick trace!) that I decided to pop it into a pre warmed oven at 170 and shut it off. I kept it there all day. I think I turned the oven on one more time somewhere in the mix.

My soap didn't go brown or discolor from the GM.

I CPOP all my soaps (100 * F and turn the oven off as soon as I put the soap in) including GM and they do not go brown. I do 50/50 water/lye and mix the GM with the oils not the lye.

I made a translucent soap once (by mistake!) I took it to light trace and CPOPed as above. It was very soft even after months cure. I thought it was the camellia oil I used. Never really worked it out other than that.
 
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