Generating heat for gelling

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Todd Ziegler

Circle Z soaps
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Tipton IN
I am wondering what oils tend to generate heat after pouring and at what percentage?

I like putting my soap through the gel phase and I know that sugars can generate heat. I know that using a heating pad and insulating the soap will increase the temperature or using a oven for generating heat are all options I can use.

I have did a lot of internet research but I can't find a concise article that covers oils that generate heat and why they create heat.

I know that coconut oil can generate heat but why does it generate heat.

I know I am asking a wide open question but if you have an article that you can point me to, I would appreciate it. I am just looking to gather as much information as I can.

My reason is simple, I love what gelling does for my soap and I am trying to settle on a few standard recipes and I want easy gelling to be a part of my recipe.
 
Coconut Oil can throw some heat if used in high amounts. My 100% CO that I use for laundry on occasion heats up quickly as do my salt soaps. I use CO at 20% and never have a problem getting full gel. I use 31-33% Lye Concentration. I also use SL in all my soaps. I just put my soap in a silicone lined wood mold, throw a lid on it and lay a double over towel over the top and sides. Always gels.
 
Well, all fats create heat when they saponify. No exceptions. What I think you really want to know is the rate at which various fatty acids saponify. I'd say most soapers would agree that soap high in coconut oil tends to saponify at a faster rate.

Speaking in general, the shorter chain, saturated fatty acids saponify more easily. Fats high in lauric, myristic and other shorter FAs => soap that tends to get hotter, all other things being held equal.

I don't know of a convenient article that will give you all this info. If there is something like this, it's likely to be a research paper looking at saponifying the pure fatty acids, not the fats from which the FAs come. Pure FAs are reliable study material; untidy fats that aren't as consistent are much more difficult to study.

On that note, however, Mobjack Bay and another soaper (sorry, their name escapes me at the moment) were talking recently about why lard tends to be slower to trace (and by corollary slower to saponify) than other similar types of fats. There were some interesting tidbits in their conversation that suggested the positions of the unsaturated and saturated FAs on each lard molecule may affect the rate of saponification. The saturated FAs were more likely to be in the more protected center position surrounded by a pair of unsaturated FAs.

I don't usually take any particular steps to make it more likely the soap will go into gel, but my soap almost always does, even though my recipes are high in lard. The few batches that don't (usually in winter when my home is in the mid 60s F), there are ways to fix that.

There are other factors that strongly affect whether a soap gels or not, and I think I'd rather play around with these factors rather than design recipes that call for lots of coconut oil. For example --

The closer the mold is to a cube or sphere, the hotter it will get in the center.

The larger the mold, the higher the center temp.

The thicker the material the mold is made of (thick wood vs thin plastic, for example) the more likely the soap will gell.

Increasing the water content reduces the temperature at which a given soap will go into gel.

Soaping somewhat hotter will increase the likelihood the soap will go into gel.
 
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Coconut Oil can throw some heat if used in high amounts. My 100% CO that I use for laundry on occasion heats up quickly as do my salt soaps. I use CO at 20% and never have a problem getting full gel. I use 31-33% Lye Concentration. I also use SL in all my soaps. I just put my soap in a silicone lined wood mold, throw a lid on it and lay a double over towel over the top and sides. Always gels.
Well, all fats create heat when they saponify. No exceptions. What I think you really want to know is the rate at which various fatty acids saponify. I'd say most soapers would agree that soap high in coconut oil tends to saponify at a faster rate.

Speaking in general, the shorter chain, saturated fatty acids saponify more easily. Fats high in lauric, myristic and other shorter FAs => soap that tends to get hotter, all other things being held equal.

I don't know of a convenient article that will give you all this info. If there is something like this, it's likely to be a research paper looking at saponifying the pure fatty acids, not the fats from which the FAs come. Pure FAs are reliable study material; untidy fats that aren't as consistent are much more difficult to study.

On that note, however, Mobjack Bay and another soaper (sorry, their name escapes me at the moment) were talking recently about why lard tends to be slower to trace (and by corollary slower to saponify) than other similar types of fats. There were some interesting tidbits in their conversation that suggested the positions of the unsaturated and saturated FAs on each lard molecule may affect the rate of saponification. The saturated FAs were more likely to be in the more protected center position surrounded by a pair of unsaturated FAs.

I don't usually take any particular steps to make it more likely the soap will go into gel, but my soap almost always does, even though my recipes are high in lard. The few batches that don't (usually in winter when my home is in the mid 60s F), there are ways to fix that.

There are other factors that strongly affect whether a soap gels or not, and I think I'd rather play around with these factors rather than design recipes that call for lots of coconut oil. For example --

The closer the mold is to a cube or sphere, the hotter it will get in the center.

The larger the mold, the higher the center temp.

The thicker the material the mold is made of (thick wood vs thin plastic, for example) the more likely the soap will gell.

Increasing the water content reduces the temperature at which a given soap will go into gel.

Soaping somewhat hotter will increase the likelihood the soap will go into gel.
I went back over my notes and the recipes that gelled nicely, had 20% CO in them and I used SL in all of them. Lard was at least 45%, with either OO or SAFO at 20% or less, 7% castor oil and 10-15% PKF.

Me and others who tried them liked the way they worked. So I will use those recipes to finalize a few standard recipes. The only question I have left is about PKF, I can't gauge the impact that it has on my recipes except for the hardness. In my recipes I used between 8-15% and I would like like to get a set percentage for the PKF, do you have any recommendations?
 
Question: What is SAFO?

There are many, many ways to ensure your soap gels fully on the first try. Even if your house is cold (my husband is from Alaska, I wear lots of layers in the winter), you can use sugar to boost bubbles and heat, you can use a heating pad under the mold, you can even do both like I do. Not to even start discussing EOs and FOs that come with lovely volcanic surprises.

I don't use that much CO, I don't use SL, and I don't use that much OO. My soaps always gel because I make sure to add enough heat into the recipe and enough external heat that I don't have to worry about it. I do, however, have to stay pretty close to my soap for about the first 4 hours after pouring to ensure they don't volcano.
 
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Remember that palm kernel oil is also a fat high in lauric and myristic acids. You have to look at the whole picture, not just the coconut oil. The info you provided says your recipes contain 30-35% high lauric-and-myristic fats.
 
And I've gotten to learn more cool soap making stuff. I think tomorrow night will be devoted to trying it out
 
@Todd Ziegler when I use both CO and PKO I use a bit more CO than PKO in my total amount. They are both cleansing so keep that in mind. I don't always have PKO though.
You were reading my mind. I was just thinking about that. It is taking so long to get PKF in. I'm 1 hour away from nurture soap and 2 hours from Wholesale supplies plus. Nurture soap does not carry them and wholesale supplies is taking 8 days before shipping. I got used to getting my supplies the next day, that I didn't stock up.
 
Question: What is SAFO?

There are many, many ways to ensure your soap gels fully on the first try. Even if your house is cold (my husband is from Alaska, I wear lots of layers in the winter), you can use sugar to boost bubbles and heat, you can use a heating pad under the mold, you can even do both like I do. Not to even start discussing EOs and FOs that come with lovely volcanic surprises.

I don't use that much CO, I don't use SL, and I don't use that much OO. My soaps always gel because I make sure to add enough heat into the recipe and enough external heat that I don't have to worry about it. I do, however, have to stay pretty close to my soap for about the first 4 hours after pouring to ensure they don't volcano.
Thanks for the tips. SAFO (safflower oil) I changed the abbreviation because I was confusing it with sunflower oil in my notes.
Remember that palm kernel oil is also a fat high in lauric and myristic acids. You have to look at the whole picture, not just the coconut oil. The info you provided says your recipes contain 30-35% high lauric-and-myristic fats.
The whole picture, is the whole reason why I asked this question lol (joke).

The ones that gelled the best had a 10% PKF w/23% Coconut oil.

I have ordered a really nice heating pad that should be here in a couple of days. I got it because I don't want to be so constrained by my recipes but I want gelling to happen. I tried the CPOP and didn't like it.

Using a lower lye concentration ( 28 - 30%) helps.
I thought that more water causes less heat? Is that what you are saying or do you mean something else? So hard to convey curiosity in a text and not sound like a jerk lol.
 
Susie wrote: "...Question: What is SAFO? ...

Todd -- You might define your abbreviations more clearly. I was confused too. I see these acronyms often enough to have a clue what they mean -- SA for Sweet Almond oil, CO for Coconut Oil, and PKO for Palm Kernel Oil, etc. OTOH, I can't recall seeing ever seeing "SAFO" as an abbreviation for SAFflower Oil before this thread.

Maybe when writing here you could define the acronym more explicitly and also choose an abbreviation that's a bit more intuitive to outsiders? Maybe something like "Saff"?

"...I thought that more water causes less heat? ..."

No, more water does not cause less heat. Increasing the water content lowers the temperature at which the soap will go into gel.
 
You were reading my mind. I was just thinking about that. It is taking so long to get PKF in. I'm 1 hour away from nurture soap and 2 hours from Wholesale supplies plus. Nurture soap does not carry them and wholesale supplies is taking 8 days before shipping. I got used to getting my supplies the next day, that I didn't stock up.

I get mine from Soaper's Choice. They are reasonable and ship fast.

I thought that more water causes less heat? Is that what you are saying or do you mean something else? So hard to convey curiosity in a text and not sound like a jerk lol.
No, Less water, less heat. More water, more heat. It gels faster with more liquid, requires less insulation.
 
My experience is that my oils have far, far less to do with the "heat" of my recipes than do my other ingredients and my process.

Soaping hot/insulating well/adding heat source=hotter batter/faster gel
Sugars=hotter/faster gel
More water=more heat
Some EOs and FOs just create lots of heat. Keep good notes so you can control the other factors to limit volcano action.

Oh, and just so you know, my heating pad is one I bought after my divorce 23 years ago. It doesn't have to be fancy, it just needs to work.
 
Susie wrote: "...Question: What is SAFO? ...

Todd -- You might define your abbreviations more clearly. I was confused too. I see these acronyms often enough to have a clue what they mean -- SA for Sweet Almond oil, CO for Coconut Oil, and PKO for Palm Kernel Oil, etc. OTOH, I can't recall seeing ever seeing "SAFO" as an abbreviation for SAFflower Oil before this thread.

Maybe when writing here you could define the acronym more explicitly and also choose an abbreviation that's a bit more intuitive to outsiders? Maybe something like "Saff"?

"...I thought that more water causes less heat? ..."

No, more water does not cause less heat. Increasing the water content lowers the temperature at which the soap will go into gel.
Thanks for the water tip, I had it backwards.

I understand what you mean about the" SAFO, but I went through the acronym thread and I couldn't find an acronym that defines wether you mean sunflower or safflower oil and since I was using both oils, I decided to create one.

My experience is that my oils have far, far less to do with the "heat" of my recipes than do my other ingredients and my process.

Soaping hot/insulating well/adding heat source=hotter batter/faster gel
Sugars=hotter/faster gel
More water=more heat
Some EOs and FOs just create lots of heat. Keep good notes so you can control the other factors to limit volcano action.

Oh, and just so you know, my heating pad is one I bought after my divorce 23 years ago. It doesn't have to be fancy, it just needs to work.
Thanks, I didn't spend a lot on my heating pad but I did get one with a variable setting. That way I can control the temperature much easier..
 
Is there any reason why we can't or wouldn't want to add a better acronym for sunflower and safflower oil to the permanent acronym/abbreviations thread? I think SUFO for sunflower oil and SAFO for safflower would be a good addition. I'm not married to the idea but the thread does state that it is under constant construction.
 
I can easily understand SUFO (although you need to see if your's is high oleic or not, because there is already a HOSO). But SA has always been sweet almond. So that is what threw me on the SAFO. I think SaffO (or SAFFO) would be much clearer.
 
I can easily understand SUFO (although you need to see if your's is high oleic or not, because there is already a HOSO). But SA has always been sweet almond. So that is what threw me on the SAFO. I think SaffO (or SAFFO) would be much clearer.
I like SAFFO & SUFO with a H in front for high oleic. Who or how could add something like that to the acronym list or should a new thread be opened up for other options.
 
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