Beeswax Flop in CP Soap

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I would bet that your batch is lye-heavy. If the beeswax was part of your original recipe when you calculated the lye amount needed, it should have been completely melted in order to combine chemically with the lye solution. Lye-heavy soap is often crumbly. Spend $10 on Amazon and get some phenolphthalein. A drop on suspect soap will turn hot pink if it has too much lye. I never use the tongue test!

If you decide to try re-batching, I would up the superfat in the original recipe with liquid oils, as you would have to raise the temperature of the rebatch very high to completely melt the excess beeswax, which risks scorching the batch. You may still have un-melted beeswax pieces. If it is lye-heavy and you use it for confetti, you will end up with an irritating, drying bar.

 
I would bet that your batch is lye-heavy. If the beeswax was part of your original recipe when you calculated the lye amount needed, it should have been completely melted in order to combine chemically with the lye solution. ... get some phenolphthalein. A drop on suspect soap...

Testing the pH of soap with test strips, phenolpthalein drops, or pH meters is not an accurate way to ensure soap is skin safe or not. The gold standard test for excess alkali is the free alkalinity titration. The zap test is a quick and easy alternative to that titration. The There are other threads on SMF that cover this issue in detail.

What I do want to say is the OP's batch is very likely NOT lye heavy unless there's some other problem in addition to whether the beeswax was melted or not.

If I add a generous 5% beeswax to my latest recipe, and if none of the beeswax was melted so none reacted with the NaOH, my calculations show the superfat in the finished soap would be reduced by only 2%.

Most soap recipe c@lculators assume NaOH is 100% pure when it's usually in the range of 92-97% so that builds in a "hidden" superfat that most soap makers don't account for. Also many people use around a 5% superfat, more or less.

These two factors make it highly unlikely the OP's batch is lye heavy.
 
This soap will have bits of unmelted beeswax scattered throughout. That will affect the texture of the soap.

I personally wouldn't sell this soap -- it wouldn't be a product I would be comfortable selling to others. But you need to do what you think is best for you.

A hot lye solution cannot melt ingredients that melt at higher temperatures such as beeswax, stearic acid, rosin, etc. There isn't enough heat energy in the lye to accomplish this task. The so-called heat transfer method is best used for recipes that are mostly liquid oils with a relatively small amount of solid fat.

This method also has a high chance of not working well for recipes that are high in solid fats. My usual recipes call for 50-60% lard and the heat transfer method simply won't melt all that lard.
I agree about the beeswax and steric acid, etc. but I use this method successfully for 90% of my soaps. My basic recipe includes cocoa butter which is hard as the dickens but I have never had a problem melting my oils. It very easily melts lard, palm, coconut oil as well as cocoa butter.
 
I'm quite sure the heat transfer method will melt a modest amount of solid fats; I've done it myself.

But, as I explained in my earlier post, this method is really not a good choice for recipes with a high percentage of solid fats, like the 50-60% lard I often use. I've done that too, and learned this the hard way.

In a situation like mine, the hot lye solution will soften the solid fats, but it won't fully melt them. I need the fats to be fully melted to get the results I want.

I'll present the heat transfer calculations if someone wants to deal with me being all math-y and science-y. But I'm not going to dump that much geekiness on this forum unless someone is truly interested.
 
I am not sure how this applies to this discussion, Bill. Lye solution is not simply liquid water, but a solution of lye in water, in this case NaOH in water. It is the very hot lye solution that is used to melt oils in the heat transfer method.

And when more than one ingredient is in the mix, the boiling point for the solution changes, as does the melting point for mixed oils, which is the issue here.
Good point and not one I was thinking of about boiling point elevation. I was simply not considering that factor and hence I was not accurate. However, I will note that I use a roughly 30% lye water solution and I have measured the temperature of the lye water mix immediately after mixing and have never measure it at over 210 degrees F. I'm not even sure it got to 205F. It certainly has never boiled.

You are correct that water boils at 212 F / 100 C at sea level. But we're talking about sodium hydroxide solutions, not water.

In the chart below, the diagonal lines are various NaOH solution concentrations. Since soap makers work at atmospheric pressure, the horizontal pink line shows atmospheric pressure. Find the point at which the NaOH concentration intersects with the atmospheric pressure. Follow that point of intersection directly downward to find the boiling point of that NaOH solution at that pressure.

The yellow line shows a 0% NaOH solution (aka plain water) at atmospheric pressure has a boiling point of 100 C / 212 F, just as you'd expect. The blue line shows a 30% NaOH solution at atmospheric pressure has a boiling point of about 117 C / 242 F.

Source: O'Brien, T. F., T. V. Bommaraju, F. Hine. Handbook of Chlor-Alkali Technology. Vol 1: Fundamentals. Appendix H: NaOH, pages 1516-1524. https://link.springer.com/content/pdf/bfm:978-0-306-48624-1/1.pdf
Nicely done explanation. I had completely overlooked boiling point elevation of the mixture. You are correct. I will say though that my ~30% lye water mix has never measured over 210F and probably not 205F. I use room temperature distilled water. It certainly never boils. It's hot, but not that hot.
 
Good point and not one I was thinking of about boiling point elevation. I was simply not considering that factor and hence I was not accurate. However, I will note that I use a roughly 30% lye water solution and I have measured the temperature of the lye water mix immediately after mixing and have never measure it at over 210 degrees F. I'm not even sure it got to 205F. It certainly has never boiled.
I have had lye solution boil over, but not with just water. It was with sugar-containing liquids and with alcohol-containing liquids. No temperatures taken, but I did learn to use taller vessels for making lye solution with those types of liquids, the first time it boiled up and over the top of the vessel into my sink. At least that experience was validated decision I made when I first started making soap to always mix my lye solution in the sink (placing the vessel in the sink to handle any potential problems inside the sink.)
 
...boiling point elevation of the mixture...

...my ~30% lye water mix has never measured over 210F and probably not 205F. ... It certainly never boils. It's hot, but not that hot....

You're conflating two entirely different processes. Your first message on this issue was regarding the boiling point of water, and my reply provided info about the boiling point temperatures of NaOH solutions.

Now you're talking about the temperature rise caused by the "heat of solution" as if it is the same thing as the boiling point temperature. This isn't correct.

The temperature rise caused the heat of solution doesn't necessarily raise the temperature of the mixture to its boiling point. If you heated your 30% NaOH solution, it would boil about 242 F, even if it never boils when you first make the solution.

When I dissolve NaOH in water, the resulting lye solution doesn't boil either. I don't expect it to.
 

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