Optimal temperature for mixing oils with lye in the CP process?

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NcDon

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What is the optimal temperature for mixing oils with lye in the CP process? I mixed the oils and lye both at temperatures between 50-55 degrees Celsius (122-131 F) in several batches and the soaps came out well. Thank you in advance.
 
I do not think there are any hard and fast rules. Some people want more time to make a design and will swirl at a lower temperature. Some soap with wax that needs a higher temperature. When I started, I was obsessed with thermometers. Now I touch my lye liquid pitcher and my oils pot and when they are just warm to the touch, I begin my session.
Also, welcome to the forum!
 
As Zing said, it depends. Higher temps will reduce the chance of soda ash, or false trace, but will also cause the soap to trace faster.

I appreciate faster trace if I’m making a layered soap, or liquid soap, especially with olive oil. I don’t appreciate it if I’m trying to create swirls.

And while I do like preventing soda ash, I’ve found other ways to combat that without using warmer oils or lye.

Bottom line, the ingredients in your recipe and your soap-making goals will determine what temperature is best for each specific batch of soap you make. :)
 
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As Zing said, it depends. Higher temps will reduce the chance of soda ash, or false trace, but will also cause the soap to trace faster.

I use 60% liquid oils (most part olive oil) and 40% solid oils and butters in my recipe. 1% ppo citric acid (dissolved in water then I add NaOH with extra lye), Water:Lye Ratio = 2.105:1, 1% ppo Panthenol, 1% ppo Sodium lactate, EO's blend 3.2% ppo. I noticed that the saponification is accelerated at 50-55 C (122-131 F), I briefly mix 4-5 times with the stick blender and the traces appear. Then I add the essential oils and additives, mix everything with the whisk and the silicone spatula and quickly pour the composition into the silicone form so that it self-levels and does not harden. No swirls. After 18-20 hours the soap is good for cutting.
 
I noticed that the saponification is accelerated at 50-55 C (122-131 F)
In the context of this sentence, did you mean that trace is accelerated with the heat, i.e., the batter becomes thick more rapidly than it tends to do at lower heat?

If your current process is working well for you, then no need to change your temperatures. Just keep in mind, using a different temperature might be wise in the future if you want to make fancy swirls, if you want to use an FO or additive that can cause overheating, etc.
 
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As others have said, there are no hard/fast rules. I soap at RT. Meaning both my oils and my lye solution is at the temperature of my room. I've been soaping for 20 years now, and I have never once used a thermometer for my soapmaking.
Some people do the heat transfer method - meaning their oils, including hard oils (oils solid at rt), are at room temperature but the lye is hot, and that will melt the oils. Others soap with both hot oils and lye.
Basically it is going to be whatever you are comfortable with, and what works for your situation.
 
...using a different temperature might be wise in the future if you want to do fancy swirls, if you want to use a FO or additive that can cause overheating, etc.
Good to know. No fancy swirls, no FO. IMO the main function of soap is washing. The emollient and moisturizing role applied to the skin (condition 56, creamy 19 and panthenol) somehow compensates for the high PH of the soap (10.2-10.5), which dries the skin and exposes it to microorganisms. Anyway, I'll set both the mixing temperature, the oils and the lye to 50C each (122F).

I’m curious to learn why you use panthenol in your cold process recipe.
Panthenol (precursor of vitamin B5) is good for skin, hair and nails. It allows the skin to retain moisture and maintain hydration. The feeling of softness of the soap upon contact with the skin is very pleasant. After washing, the skin does not remain dry (tested). It also helps to heal wounds and burns. The soap is for personal use and I thought it would be good to improve its quality.

As others have said, there are no hard/fast rules. Basically it is going to be whatever you are comfortable with, and what works for your situation.

That's how i got used to. To mix oils and lye at high temperature in CP processing. It works and it's not hard. I don't think high temperature it affects the additives I use.
 
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The emollient and moisturizing role applied to the skin (condition 56, creamy 19 and penthanol) somehow compensates for the high PH of the soap
Soap by definition isn't moisturizing, despite how the calculator numbers are described. It can be less drying, or less stripping, but not moisturizing. If you were in the US, the use of the term "moisturizing" would set you up for problems with our regulators, unless you follow the labeling and other rules for using that term.

However, since your soap is for personal use, and you are not in the US, maybe you don't have to worry too much about that. Still, your terminology about certain ingredients "compensating for the high pH" is probably the better way to put it.

I really do appreciate that you shared how nice the panthenol is in the soap. So far, I've only used panthenol in syndet shampoo bars, and solid hair conditioner bars. You've convinced me to try a bit of it in a small test batch of bar soap. It's very expensive here, so even if it is very nice, I'll have to limit it to personal use bars, or making it by request for friends who are willing to pay the ingredient cost.

Thanks!
 
Panthenol isn't stable at high pH such as soap, or at high temps for long:

"Pantothenic Acid - an overview | ScienceDirect Topics
https://www.sciencedirect.com/topics/chemistry/pantothenic-acid
Panthenol is added to the water phase and is stable to heat during manufacturing (up to 75°C), although prolonged heat should be avoided. It is stable in the pH range from 4.0 to 7.5 (optimum pH 6.0). "
 
What is the optimal temperature for mixing oils with lye in the CP process?
There really isn't one to be honest. When first starting out, 110F for both Oils/Butters and Lye Solution is often recommend as it ensures that the Oils/Butters are fully melted, lessens the chance for false trace and makes for a more successful soaping experience. Once you develop your own recipe (which every soap maker does, even if it's only a small tweak) and style, you will find the optimum temperature.

For me, I Master Batch my Oils/Butters and Lye Solution. I usually heat my Oils/Butters to around 120F, my Lye Solution is around 70F which puts my batter temp at around 90F. This is for my Regular Soap, my Goat Milk Soap batter is usually around 80F as not to scorch the GM.
 

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