Does Castile Soap Really Take That Long to Harden?

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MickeyRat

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I've seen many posts on here saying Castile soap takes a long time to harden. I recently made my first version of it and it seems to be hardening at least as fast as my usual recipe perhaps a bit faster. My understanding is that Castile soap is pretty much all olive oil. That's what I did with a slight variation.

Recipe 33 oz batch

95% Olive oil
5% Castor oil

5% KOH 95% NOH for the lye

1 tsp salt and 1 tsp sugar in lye water

Maybe it'll slow down but, it's only been a couple days and right now, it's almost hard enough to use. I'll still let it cure for a couple months but, I didn't expect this result. I know I added the salt to promote hardening. I've convinced myself that works but, I didn't expect the effect to be that dramatic. So, I don't know what to make of the way it's hardening up.
 
Most soap makers give Castile a longer cure time. The reason for a longer cure is a harder bar that lasts longer, gets milder and has better lather.
 
Thanks for the reply. I can let it sit for a while. I made this at the end of my yearly spasm of soapmaking for the Christmas season. As for hardness, it appears to be doing fine so far. I'm hoping the castor and KOH will help with the lather.
 
I've had castile take 2 days to harden, I've also had harden so fast that I was barely able to cut it a few hours later.

Most people are going to recommend a 6+ month cure for castile.
 
Just remember there is a difference between cure time and hardening time. When we talk about hardening a bar, we are talking about the time it takes for the soap to get hard enough to cut, without damaging the soap because it was to soft to cut.

Cure time involves evaporation and a chemical process that takes place in the soap.
 
This post reminded me that i had some 4 month old castile curing in the spare bedroom lol. I just tried a bar. There is nothing special added as this was one of my first soaps. So far i dont like it. It got bubbly, but it took some work to get bubbles.

It is a nice pretty white though...
 
Hardening and curing are not the same thing.

How long it takes to set up (harden) enough to unmold and cut into bars, depends more on your formula. Lye concentration (or the amount of lye to water ratio), the addition of Sodium Lactate or other hardeners will impact how fast it sets up and hardens prior to cut.

But curing, although it does involve water loss, is not the same thing at all, as mentioned by posters above. Many soapers who cure Castile for years, say it only improves with a longer cure. Not everyone likes Castile soap, however, so the long cure isn't worth it to them. I like it and find it does benefit from a longer cure.

If you keep some bars aside for the long haul, and test some periodically over the course of the cure, you can come to your own conclusions about how it performs as a soap with shorter and longer cure times, and various stops along the way.
 
Mine did not take a long time to set up -- did it just as quickly as any soap -- however it's NOT soap yet. If you try to use it, it's just slimy and doesn't lather at all. I've been told that it take about a year for it to actually become soap. I'm still waiting.
 
I think some types of soap benefit from a longer cure time to be at their best. I've tested a few different types of soap over 1-2 years (a few even longer), looking at the skin feel and lather. I can attest to definite changes over that time, especially during the first year.

The soaps I've tested that seem to benefit from a longer cure than the usual 1-2 months tend to be soaps made using mostly or all just one fat. Mostly lard, mostly high oleic fats (olive, sunflower, etc.), mostly coconut oil, etc. I think of these as being a little more "one dimensional" than soap made from a balanced blend of several fats that provide a wider range of fatty acids.

The lesson that taught me the benefit of a longer cure time was a 85% lard, 15% coconut oil soap that didn't lather much at all through the "normal" cure time of 1-2 months -- it was really disappointing at that point -- but it lathered very nicely at about 1 year.

I don't see a whole lot of change after that 1 year mark, no matter what kind of soap it is, including castile type soap. I still have some of the Andalusian superlye soap we were making in 2016, and I test it from time to time. Can't say it's any much different now than when it was a year old.
 
I super-fat a little maybe 6%, but the 100% coconut oil soap has never seemed harsh or irritating -- even when it's quite young.

I already have plans for this weekend, but the weekend after that, I will probably make a couple batches of soap -- so it has more time to cure. I plan to make some more Castile in hopes that I'll like it a year from now.
 
@mensasnem 100% CO will lather 1 day out. At only 6% SF it would strip my skin off. Even at 20% without a good cure it’s too drying for me. Though I live a good salt soap.

Castille dries my skin no matter how long of a cure.
 
Thanks for the input. I could have sworn that I saw posts that specifically said Castile took a long time to harden. That's why I was surprised. This is my yearly soap for the holidays spasm. I have plenty around to let the Castile sit for a while. It does make a pretty white bar. :)
 
I've seen many posts on here saying Castile soap takes a long time to harden. I recently made my first version of it and it seems to be hardening at least as fast as my usual recipe perhaps a bit faster. My understanding is that Castile soap is pretty much all olive oil. That's what I did with a slight variation.

Recipe 33 oz batch

95% Olive oil
5% Castor oil

5% KOH 95% NOH for the lye

1 tsp salt and 1 tsp sugar in lye water

Maybe it'll slow down but, it's only been a couple days and right now, it's almost hard enough to use. I'll still let it cure for a couple months but, I didn't expect this result. I know I added the salt to promote hardening. I've convinced myself that works but, I didn't expect the effect to be that dramatic. So, I don't know what to make of the way it's hardening up.

I true Castile soap is just Olive Oil and your lye solution made with distilled water and Sodium Hydroxide (I’m a purest). Any other ingredients make it a Bastille.

Your soap may be hard (most soap is hard with 18 - 24 hours), but until it cures a bare minimum of four weeks, it’s really not ready to use. Sure, you can use soap once it’s past the zap test...it’s soap, but it won’t be a very good bar of soap and won’t last long. Don’t understand why you are using KOH, then adding soap to ‘harden’ your bar. Just skip the KOH.
 
Your soap may be hard (most soap is hard with 18 - 24 hours), but until it cures a bare minimum of four weeks, it’s really not ready to use. Sure, you can use soap once it’s past the zap test...it’s soap, but it won’t be a very good bar of soap and won’t last long. Don’t understand why you are using KOH, then adding soap to ‘harden’ your bar. Just skip the KOH.

A couple clarifications. The KOH is not to make it harder. It makes soap lather better, You're free to disagree but, I've tried it both ways and I'm convinced it works. The sugar is supposed to help with lather too. I'm not as convinced about that but, I've always done it. I do use salt in the lye water to promote hardness. I know that's a practice some people disagree about but, I've tried it both ways... I cure all my soaps at least 6 weeks and usually a couple months. I intended to do the same with this batch. From what I'm seeing in this thread, that's probably not long enough.

I guess I am making Bastille soap rather than Castile soap. I'm no authority about that. :)
 
Although I tend to think of Castile a soap made with no other oil than Olive Oil, the US courts made a decision in 1932 about what can be called Castile (go figure, someone had to sue about it), and here in the US your soap certainly passes the test as per the court's ruling. Here is the wording by the Federal Trade Commission on the topic:

Castile Soap.
—One of the first, if not the first, hard cake soaps that entered largely into commerce was made from pure olive oil and soda with no admixture of any other fat . Such a soap was known as Castile, Marseilles ,or Venetian soap .Modern trade practices and manufacturing methods had so altered the accepted meaning of the term “castile” as to result in a ruling in 1932 by a Federal court that a product labeled or sold as “castile soap” may contain oils and fats other than olive oil. There are soaps made entirely from coconut oil which are sold as coconut castiles or hard-water castiles. Other castiles are made from a mixture of coconut oil and tallow or other fat. When made from olive oil, it is sold as olive-oil castile. Castile soap for toilet or household use is usually sold in unwrapped, unper¬fumed bars and in small cakes or bars both wrapped and unwrapped. It is generally made by the full-boiled process and is often drawn directly from the kettle without “crutching,” but is sometimes crutched a little, or even enough to make it float, and is sometimes milled. There are also on the market powdered castile soaps and “liquid castile soaps.” The latter are intended for hospital use and are water solutions of potash soap, generally made wholly from olive oil, or a mixture of olive oil with about 10 to 20 percent of coconut oil and potash.

(source)


The term 'crutching' soap is defined here as stirring. Although in other searches it seems to indicate the addition of brine is needed to make the soap float. The salting-out method results in soap that floats. So I am not really sure what was meant by 'crutching' in the above FTC quote. But, if brine is added to Castile to create a floating soap, per the above definition, it is still Castile soap according to US legal standards.


If you choose to be or are a soap making purist, then calling your soap 'Castile' might be wrong; but if you sell your soap and don't want to have to worry about the FDA warning you that you are misrepresenting your soap by labeling it as Castile, then you have nothing to worry about in the US. Elsewhere may be another story.
 
Castile with a capital "C" is soap made in the Castile region of Spain. As Earlene has pointed out, the purist's definition of castile as 100% olive oil is something only a soap maker is inclined to use. And that's not a consistent thing -- many soap makers use castile to mean any veg oil soap, because that's the accepted meaning of "castile" in worldwide commerce.

IMO, even in soap making circles it's probably best to just spell it out as a 100% olive oil soap so there's no possible reason for confusion. It would be nice to dispense with the recurring drama about whether a soap is a castile or a bastile or whatever.

***

And the idea of KOH not being acceptable in a purist's castile is not historically accurate. Castile with a capital "C" was made using an alkali made from the ashes of certain sea coast plants. This alkali was high in potassium (K) but also richer in sodium (Na) than typical wood-ash lye because the sea coast plants had a higher sodium content in their tissues. Also salt (NaCl) was sometimes used to salt-out this soap if a harder finished soap was wanted. That would also have raised the sodium content of the finished soap, but even salting-out would not have removed all of the potassium in the soap.

So potassium was a normal ingredient in Castile with a capital "C" soap as it was historically made. So if a person is wanting to be a purist about this, it's more accurate to use a mixed potassium and sodium alkali to make this type of soap than to use a pure sodium alkali.

***

The use of 5-10% KOH in a soap with the rest being NaOH is not for hardness. Not sure where this idea is coming from, but it needs to be nipped in the bud before it becomes an entrenched "fact" on the soaping internet. KOH will tend to SOFTEN a soap, not harden it.

Some soap makers include a small amount of KOH as a way to increase the solubility of soap, so the soap can dissolve and mix more easily with water. The benefits of KOH are best seen in soaps high in stearic and palmitic acids (lard, the butters, palm, etc.) and soaps high in oleic acid (olive oil and other high oleic oils).

The use of a small amount of KOH will not be helpful for soaps that are already highly soluble and can mix easily with water -- in other words soaps high in myristic and lauric acids (coconut oil, palm kernel, etc.)
 

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