CP soap thickening (mashed potatoes consistency) immediately

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blue54899

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Hello all,

I am running into an issue with a shave soap formula i have been working on:

50% Stearic acid
20% Beef tallow
10% Kokum Butter
10% Shea Butter
5% Coconut Oil
5% Castor Oil

60% KOH
40% NaOH

Water (tap) 38% of oils


I melt the oils/butter completely (about 75C) and then let cooll to about 55C. I add the NaOH (it's a 50/50 solution) at room temperature, and KOH maybe a little above room temperature (fully disolved). As soon as I add the NaOH and KOH, the entire batter seizes and becomes mashed potatoes texture. It is very thick, but I am looking to create a batter that is thin and pourable (into moulds, for swirling, etc). Does anyone have any ideas on why this is happening and on any alternatives? Thanks
 
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Stearic acid is a fatty acid. It reacts nearly instantly with alkali like NaOH and KOH.

That fast reaction time is why shave soap made with stearic acid is prepared with a hot process method.

You will need to reformulate your recipe to eliminate the stearic acid and use only fats if you want to use a cold process method, get a longer working time, and the option to do fancy swirls.
 
I am not understanding how you could get the oils and butters completely melted at 75F. The melting point of stearic acid is 155-160F.
 
Stearic acid is a fatty acid. It reacts nearly instantly with alkali like NaOH and KOH.

That fast reaction time is why shave soap made with stearic acid is prepared with a hot process method.

You will need to reformulate your recipe to eliminate the stearic acid and use only fats if you want to use a cold process method, get a longer working time, and the option to do fancy swirls.
Do you think something like 20% or 30% stearic acid would still lead to instant trace? Or are you suggesting that I just have a mix of tallow + butters/fats instead?
 
My apologies, I meant 75C!
I thought it might be either C, or you meant 175F. Thanks for clarifying! I agree with DeeAnna that you will have to soap hotter, especially if you want to use stearic acid (which is recommended for a good shave soap). It traces fast no matter what.

Also, instead of using 38% water as percent of oils, change your setting to somewhere between 22% and 25% lye concentration. That will give you more water, which you need for hot process, and especially shave soap. I've never been able to swirl my shave soap, but I've never made it without stearic acid.

One last note :) I also recommend using distilled water; tap water has a lot of impurities that can cause your soap to become rancid, or not lather well.
 
Do you think something like 20% or 30% stearic acid would still lead to instant trace? Or are you suggesting that I just have a mix of tallow + butters/fats instead?
I meant exactly what I said -- if you want a recipe you can make with a cold process method so you can do pretty swirls, you will need to reformulate to eliminate the stearic acid and only use fats.
 
I use a similar recipe for my shave soap and yes, stearic acid makes it trace FAST. If you want to keep your recipe, add your lye hotter (I like both oils and lye around 55 - 60C), do it hot process and use a spoon to stir to trace instead of a stick blender. I add sodium lactate after the cook to give it some more fluidity.
 

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