I bought a pound of stearic acid off Amazon to try to get the longevity of my soap up. The past 2 times I've used it, my soap instantly came together and was very hard to mix. The first I think it was 15-20% of my oil weight. The second time it was 5% of my oil weight. How do I use stearic acid and at what amounts should I use it to maximize the effect? Or should I just forget about using it?
Stearic Acid question
- Thread starter Hippie13
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Saponomancer
Professional Geek
To be honest I wouldn't use it unless I was hot processing, it always seizes on me.
Stearic acid is a fatty acid and fatty acids and lye (NaOH or KOH) react very quickly with each other. That is the nature of fatty acids, and there is no way to prevent it -- you can just do your best to work with it.
Some people do okay with a cold process soaping method and maybe 2-3% stearic. But if you really want 5% to 20% stearic in your soap, you probably should consider using a hot process method instead. That's how most of us make shaving soap with high levels of stearic acid.
You might ask for feedback on your recipe -- if you aren't getting the longevity, there are other ways to tweak a recipe to make the soap longer lasting besides adding stearic (or beeswax).
Some people do okay with a cold process soaping method and maybe 2-3% stearic. But if you really want 5% to 20% stearic in your soap, you probably should consider using a hot process method instead. That's how most of us make shaving soap with high levels of stearic acid.
You might ask for feedback on your recipe -- if you aren't getting the longevity, there are other ways to tweak a recipe to make the soap longer lasting besides adding stearic (or beeswax).
My recipe was 25% castor oil, 15% cocoa butter, 30% coconut oil, 25% olive oil, and 5% stearic acid. I do want a longer lasting bar so I'm open to all help. I don't have to use stearic acid at all or at any percentage. The first time I used it, I tried CP. This second time it was HP and went easier.
I can see why your recipe isn't lasting very long. The only thing besides the stearic acid that's going to help in the longevity department is the cocoa butter. I take it you don't want to use palm, tallow, or lard?
That's also a lot of castor -- most people use 10% max for typical recipes. Can you explain your thoughts about that?
That's also a lot of castor -- most people use 10% max for typical recipes. Can you explain your thoughts about that?
Actually I have some palm oil and kernel flakes so I can use either if I need to. I used that much castor to get the conditioning up. I made an HP bar and I really liked the color and scent but when I used it, my skin felt so dry. I know that castor is good for conditioning and leaving the skin feeling good.
I'd also love to get my hands on some lard in the future.
bumbleklutz
Well-Known Member
If you're finding the soap drying, it might be the coconut oil. Coconut can be VERY cleansing and strip the natural oils from your skin. Also, although I love castor oil in soap, at much more than 10% it can make a soft sticky bar. You might try lowering the castor to 10%, lowering the coconut to 20%, lowering the cocoa butter to 10%, leaving the olive at 30% and adding 30% palm oil. That will give you a harder and longer lasting bar.
I've never had any luck using stearic acid in cp. I just end up with soap-on-a-stick every time I've tried.
I've never had any luck using stearic acid in cp. I just end up with soap-on-a-stick every time I've tried.
When an oil becomes a salt of fatty acids (aka soap) the properties can change. A LOT. Take coconut oil - as an oil, lovely on the skin. As sodium cocoate, it is very harsh on the skin.
Castor Oil has much water affinity and it's not very gentle to the skin in big quantities. Stearic Acid is good for stabilizing lather, although it's difficult to manipulate in CP. I made a 15% stearic acid soap once, I had to keep everything above 70°C until it accepts to mix with the rest of the oils. It was really a painful process -- turned out HP Hero, but the result is still very nice for the skin (super creamy, leaves you as silk!). Soap bar qualities of HP and CP are pretty the same, a drying bar is more likely caused by the recipe instead of the process.
Don't confuse the name "conditioning" with the actual performance of the soap bar. All the "conditioning" number means is the total percentage of oleic, linoleic, linolenic, and ricinoleic fatty acids. They had to give it a name, and "conditioning" stuck, but the name is rather misleading to newer soapers.
Castor oil SOAP isn't the same as castor OIL, as others are pointing out. Many newer soapers want castor to be the miracle cure for lots of bubbles and lots of "conditioning" in their soaps, but a high % of castor in a soap recipe doesn't necessarily work all that well. Far better to let the main players -- myristic, lauric, palmitic, stearic, and oleic acids -- be the stars in a soap recipe. Let ricinoleic acid (the fatty acid from castor oil) be a supporting actor.
The recipe you shared -- thank you! -- could be tweaked to make it more balanced. Your use of stearic acid is a step in the right direction, but I'd use a fat high in stearic acid rather than stearic itself. Add palm, tallow or lard to your recipe in place of the stearic and most or all of the castor. You'll get a nice bar of soap without the trouble that stearic acid brings to your soaping. Your soap will also benefit from the other fatty acids that these fats add to a recipe.
If you like that much coconut oil in your soap, then keep it, but if your skin feels overly dry or tight when using this soap, then consider lowering the coconut oil too.
Castor oil SOAP isn't the same as castor OIL, as others are pointing out. Many newer soapers want castor to be the miracle cure for lots of bubbles and lots of "conditioning" in their soaps, but a high % of castor in a soap recipe doesn't necessarily work all that well. Far better to let the main players -- myristic, lauric, palmitic, stearic, and oleic acids -- be the stars in a soap recipe. Let ricinoleic acid (the fatty acid from castor oil) be a supporting actor.
The recipe you shared -- thank you! -- could be tweaked to make it more balanced. Your use of stearic acid is a step in the right direction, but I'd use a fat high in stearic acid rather than stearic itself. Add palm, tallow or lard to your recipe in place of the stearic and most or all of the castor. You'll get a nice bar of soap without the trouble that stearic acid brings to your soaping. Your soap will also benefit from the other fatty acids that these fats add to a recipe.
If you like that much coconut oil in your soap, then keep it, but if your skin feels overly dry or tight when using this soap, then consider lowering the coconut oil too.
I've read that coconut oil should be used around 30-35% of your oils so that's why I'm using such a high amount. I'll lower it for my next bar and see how everything turns out. I'm going to use the recipe provided in an earlier comment and make some HP today.
There are many reasons why one might use that much coconut oil; some reasons are quite practical and realistic and others are soaping myths. Regardless, the real point is this -- if a 30% to 35% coconut oil recipe works for you and your skin, that's all that matters.
But if your skin feels a little tight and dry with this type of recipe, the usual wisdom is to reduce the amount of fats high in lauric and myristic acid -- coconut, babassu, and palm kernel. The trade off is that these fatty acids contribute to fast, bigger bubbles of lather, so by reducing them, the soap may lather less. But there are tweaks one can use to encourage bubbles if you miss them -- examples include adding a source of sugars or starches, using a small amount of KOH along with NaOH, etc.
But see how your revised recipe works for you first before leaping into the tweaks!
But if your skin feels a little tight and dry with this type of recipe, the usual wisdom is to reduce the amount of fats high in lauric and myristic acid -- coconut, babassu, and palm kernel. The trade off is that these fatty acids contribute to fast, bigger bubbles of lather, so by reducing them, the soap may lather less. But there are tweaks one can use to encourage bubbles if you miss them -- examples include adding a source of sugars or starches, using a small amount of KOH along with NaOH, etc.
But see how your revised recipe works for you first before leaping into the tweaks!
I finally made my soap. I scented it with lavender with a little bit of vanilla extract and it smells good. Skin still felt a little tight after using it in the shower so I may decrease the coconut oil to 15% and do 5% shea butter to make up for it. What other kind of fats should I try for to make my soap more skin nourishing?
Kittish
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How long did you wait between making the soap and trying it out? You really should let the soap actually cure before passing judgement on it. A young soap is going to be harsher than a fully cured one. Even if you're using hot process, the soap needs to cure for at least 4-6 weeks, if not longer.
Ditto what Kittish said^^^.
The "earliest best" for my CP is 4-weeks of cure, and for my HP it's 6-weeks, because of the water differential (my CP has much less water to evaporate out than my HP).
The amount of water in a soap has a direct effect on the time it takes for crystaline structure inside the soap to develop and organize/restructure itself during cure. If you ever wanted to know what's microscopically going on inside of a soap as it cures, here is an excellent post by our DeeAnna on the subject:
http://www.soapmakingforum.com/showpost.php?p=634104&postcount=51, which to me goes a long way in explaining why a well-cured soap lasts longer, is more bubbly and more mild than a younger soap.
In a nutshell, the restructuring and stabilization of the crystalline structure within a bar of soap (what I like to call the 'soapy matrix') can only begin when a sufficient amount of water evaporation has taken place. In other words, the real curing process doesn't get down into the full swing of the nitty gritty until there's not as much water hanging around.
That's why so many of us here on the forum are so enthusiastic in encouraging newcomers to the craft to not be tempted to skimp on a good cure (most especially with HP) and to not judge the performance or the 'feel' of a soap that's only a few weeks old. A soap's true identity will not reveal itself until many weeks have gone by.
IrishLass
The "earliest best" for my CP is 4-weeks of cure, and for my HP it's 6-weeks, because of the water differential (my CP has much less water to evaporate out than my HP).
The amount of water in a soap has a direct effect on the time it takes for crystaline structure inside the soap to develop and organize/restructure itself during cure. If you ever wanted to know what's microscopically going on inside of a soap as it cures, here is an excellent post by our DeeAnna on the subject:
http://www.soapmakingforum.com/showpost.php?p=634104&postcount=51, which to me goes a long way in explaining why a well-cured soap lasts longer, is more bubbly and more mild than a younger soap.
In a nutshell, the restructuring and stabilization of the crystalline structure within a bar of soap (what I like to call the 'soapy matrix') can only begin when a sufficient amount of water evaporation has taken place. In other words, the real curing process doesn't get down into the full swing of the nitty gritty until there's not as much water hanging around.
That's why so many of us here on the forum are so enthusiastic in encouraging newcomers to the craft to not be tempted to skimp on a good cure (most especially with HP) and to not judge the performance or the 'feel' of a soap that's only a few weeks old. A soap's true identity will not reveal itself until many weeks have gone by.
IrishLass
neonstudy
Well-Known Member
You should try lard, it make soap really moisturizing.
