Castile Soap Turned Out Crumbly

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Nov 12, 2016
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I'm new to soapmaking and am looking to make a Castile bar soap using only organic extra virgin olive oil and lye (I've been buying one, but it's so expensive!). I decided to use a hot process method with a crockpot, as I know Castile soap and Savon de Marseille were traditionally made in cauldrons. Today was my first attempt, and the bars turned out hard and crumbly, not smooth like the Castile soap I've been buying.

I didn't blend for very long with my hand mixer, so I wonder if it didn't emulsify properly? Or I didn't stir often enough? I tried using the stick blender a little later in the process, but it still seemed to have a curdled texture. Also, afterwards, I read that you should insulate with plastic wrap or a dishtowel to retain water, but my original recipe did not say that, so I didn't. In fact, it said the opposite, that I should remove the cover towards the "mashed potato" stage, so it's possible too much moisture escaped or I overcooked it. It is, however, lathering well with water, so I'd venture to say it's usable--I hope!!

So my two questions are:
1) How do I know if my soap is usable?/Is there anyway the lye is still active?
2) What would cause a crumbly or curdled looking soap?

I so appreciate your guidance!
Welcome savondemarseille! :wave:

Can you post how much olive oil, water and lye you used? That will give us a good trouble-shooting foundation to work off of.

In the mean-time, to answer your questions:

1) Doing a zap/tongue test will tell you if your soap is safe to use. Here is how to conduct a zap/tongue test:

To conduct a zap/tongue test, just take a pea-size or smaller amount of your soap (or soap paste) and lather it up between two fingers under running water.....

Next, take some of the lather and gently touch it to the very tip of your tongue......

If you feel a zappy sensation similar to the feeling you would get from touching the tip of your tongue to the terminal of a small 9-volt battery, or the prickly sensation you might feel from touching a drop of hot pepper sauce to the tip of your tongue, that means that there is still unreacted lye in the soap, and it is not safe to use just yet (rinse your tongue off in a glass of water afterwards if you need to).

2) A few different things can cause a crumbly, curdled soap, such as too little water, and/or too much lye, or even certain fragrance oils, etc.... The more you tell us about the amount of ingredients you used in your batch, the better we will be able to pinpoint the culprit.

IrishLass :)
Thanks so much, IrishLass! I used 2 lbs of olive oil, .76 lbs water, .3 lbs lye. I measured very carefully with a kitchen scale.
Thought a picture might help too!

Welcome to the forum, sdm!

Good thinking posting the picture. I am guessing your soap was overcooked or had too little water. That would be good news because if it was true, you'd have usable, functional, fine soap. Did your tongue get zapped?
Thank you, Carabou! It didn't zap me. I don't know what soap tastes like, but it tastes salty. I don't think it burned my tongue. Is there anything I can do to fix it? Can I rewatch and add water? Or is it not worth it?
Definitely rebatch! That's all part of the fun. My guess is also that you overcooked it and evaporated too much water.

Rebatching can be strange and unpredictable from my experience and the water and soap might not want to mix at the start, but if you keep stirring them together as it cooks, they'll eventually get there. I do a hot process shaving soap and I have had to add more water and cook again.

Also rebatching should elimante any chance of leftover lye pockets that you may have been worried about from not fully blending.

That being said, I've never made a pure castille. Good luck and have fun.
Thanks, Jimsteel! Is it too late to rebatch at a certain point?

Also, new development! I tested the bars with litmus strips and they have a pH of 10. That's pretty high! I've read that when you test, the reading is probably a bit lower than the actual ph of the bar. The Castile soap I bought is a ph of 7 or 8. Can anything be done about this now?
No lye-based soap will be 7 - soap is a salt of fatty acids and so will always be alkaline to a greater or lesser degree, depending on the recipe. The most important thing is the actual recipe being balanced and there being no excess lye left over - to test for the latter, you can zap test the soap.
Thanks, The Effacious Gentleman. I zap tested and it seemed fine, but is it possible there are still pockets of lye? Also, I found the soap to be drying compared to the Castile soap that I bought.
As long as I've been reading SMF, I've seen some pretty ugly, poorly made soap, but I've not seen "lye pockets" if the soaper has made any reasonable effort to make the soap properly. But if you're worried, then do a zap test in a number of different spots on the soap. Cut a bar apart and zap test the interior too. That should reassure you one way or the other.

You need to let this soap fully cure before judging it as far as mildness, lather, and longevity. Patience, grasshopper. :)
My rule of thumb for any soap is that it should be cured 4-6 weeks for reasonable lather, mildness, and longevity. Soapers with more experience with olive oil soaps than I have will tell you this type of soap needs at least 6 months and preferably more to really shine.

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