Castile 95%NaOH 5%KOH calculations help

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Ladies and gents so you separate the water mix lye and koh then put them together in one bowl to add to oils or separately? Very interesting tread
Can any soap be done this way or just high oleic soaps?
 
I don't mix my KOH and NaOH separately. I have used KOH 60%, NaOH 40% for liquid soap mix, so this may be different for solid soap, but I mix my NaOH with the water first, then add the KOH to the hot NaOH/water mixture. Saves a step and a dish.
 
Dahlia, I do my NaOH as a master-batch of 50/50 lye to water & took my NaOH from there as per procedure of measuring masterbatched lye. Then I mixed a 50/50 KOH to water with some of the additional water called for in the recipe. Then I mixed the two lyes together. They heated up. Then I added the remaining water (as per calculations based on the recipe and master-batching protocol.)

I have used the 95%/5% Dual Lye method for several soaps since this first one, and I do like the process. But I am considering making a master-batch of KOH, but have not done so as yet because I don't want to accidentally end up using the wrong solution when I make soap at some time in the future. So then I though maybe I should figure out how to make a master-batch of the Dual Lye solution itself and just make enough for a few batches at a time. So far it is only a thought and I haven't put a lot of time into figuring out how to do the math on the latter.

As to your other question about doing this with soaps other than high oleic ones, I am too new at this method to answer that. In another thread I believe I read that DeeAnna is experimenting with doing the dual lye method with her high-lard soaps.
 
I used it only for 100% avocado oil soap. That oil traced so much faster than olive oil I was shocked. It also lead to slimy soaps with nice lather.
 
I made batches of the 95% NaOH, 5% KOH soap yesterday and today with the following oils:

Lard 65%
Olive Oil 15%
Coconut Oil 15%
Castor Oil 5%

Superfat 5%

The one I made yesterday, I used no sugar. The batch I made today had my standard 0.5 oz/32 oz oil sugar addition. I have plenty of non-dual lye soaps to compare it to, so I will have a good comparison. The batch yesterday took a long time to trace with Cinnamon Candies from WSP, and the batch today with Pear Glace from WSP traced within seconds. It smells great, but is currently sitting in an ice water bath so it does not volcano.
 
Reporting on my impressions of using this soap at 6 months cure with a comparison to 15-month cured Castile. For the younger Castile, I used the pink one, which is 100% OO of the Kirkland brand, which comes from Costco. The older Castile was made with Sam's Club OO because that's what I had on hand (I don't actually live very close to a Costco, but I do live close to Sam's Club.)

I don't have a 6 month young bar of single lye Castile to compare it to, but I do believe my results belie the statement that a 4-6 week cure for dual lye Castile is sufficient to eliminate slime or that has cured enough to be mild.

Other than the lye composition, the amount of water and the addition of micas to the newer soap, the recipes are exactly the same. Olive Oil and water, same 5% SF, both done CP (although at this point I don't think that would matter.)

Single Lye Castile (15 months of age):
Copious large to medium bubbles; absolutely no slime; fairly creamy lather than starts a little slower and takes a bit longer to become creamy, but feels very good on my skin. After washing and rinsing, there seems to be a residual conditioning or nourishing feel to my skin that lasts nicely.
Notes about the bar & recipe: I made this with full water per SoapCalc's default. It is softer, not yet 'rock hard' like the pink bar below.

Dual Lye Castile (95% NaOH + 5% KOH) (6 months of age):
Slightly smaller, but abundant bubbles; copious thick and creamy lather; slime forms when I hold my palm flat on the bar and lift it away, breaking at about 1 to 1.5 inches from the surface as I lift my hand; HOWEVER, this slime goes away when I used the same bar twice and I had a hard time re-creating the slime after the initial one minute of soaping up my hands. After using this 6-month young Dual Lye Castile, my skin feel dryer than I like. Not as mild and not as 'conditioned' or 'nourished' or whatever that feeling is when a soap doesn't leave my hands feeling like they would benefit from some lotion.
Notes about the bar & recipe: I made this with a [40% Lye Concentration] so less water. It is very hard, although it did bow a bit while drying, which the other one did not, but I suspect that has to do with not turning the bar as frequently to prevent bowing.


The temperature of the water seems to make no difference whatsoever on these findings. At first I used warm water. Later I re-tested with cold water accidentally, but it was actually interesting to see that it made no difference. Then I repeated it with warm water again almost immediately. That's when I discovered the slime is harder to 'find' in the dual lye Castile when washing the soap, rinsing the soap and re-washing again right away.

Also of interest, is that when my hands felt dryer than I like after using the dual lye Castile, about 10 minutes later I simply washed again with the 15-month old Castile and my hands feel better again. Odd that.

In any case, I do believe that even if some say you can use a Dual Lye Castile earlier (at 4-6 weeks), I would NOT recommend it. Even at 6 months, it's not anywhere near as mild as it should be in my opinion.
 
On another note, I've just started reading the thread, 'Deanna, I have a question....' wherein several members here made a lye heavy Castile recipe shared by AnnaMarie, which produced a very mild and slime-free Castile. Besides the excess lye, the excess water seemed to be extremely important as well. I am only on page 24 of the thread so far, so have not yet reached the long-term reports of the experiment, other than AnnaMarie's which were long-term from the start of the thread. But it leads me to wonder if my dual lye Castile would have benefited more from a higher water content. I used a [40% Lye Concentration] so obviously not a lot of water.

I may try this recipe again with a lot more water and see how it turns out at similar intervals to this one for comparison.
 
On another note, I've just started reading the thread, 'Deanna, I have a question....' wherein several members here made a lye heavy Castile recipe shared by AnnaMarie, which produced a very mild and slime-free Castile. Besides the excess lye, the excess water seemed to be extremely important as well. I am only on page 24 of the thread so far, so have not yet reached the long-term reports of the experiment, other than AnnaMarie's which were long-term from the start of the thread. But it leads me to wonder if my dual lye Castile would have benefited more from a higher water content. I used a [40% Lye Concentration] so obviously not a lot of water.

I may try this recipe again with a lot more water and see how it turns out at similar intervals to this one for comparison.

That recipe is pretty tricky. The lye grains out the soap just like salt would. The result is that it won't trace, or you force it by blending and it's still too weepy in the mold. The purpose of the lye excess, even though it will cure out, is unclear. I don't think we have heard of any CP soap being made like that anywhere, at least intentionally.

I don't know if I'll ever have time to try, partly because I don't totally trust that the instructions we have are correct or worthwhile, but I think I know how it could work, in principle. Basically, you don't want the concentration of the caustic in the liquid to be high enough to salt out the soap. You would probably have to add all or most of the water up front, except for the part you use to create a concentrated lye. Then you would add that slowly, allowing time for alkali to be used up before adding more.

What makes me think the instructions are wrong or misleading is that the process would take forever at room temp. That would be better for HP. The amount of excess lye in the recipe could maybe even inevitably cause the soap to separate by the time you get it all in.

The fact to understand in all this is that sodium hydroxide is even more effective at throwing soap out of solution than sodium chloride. From knowing what the fully-boiled soap makers do (or did), I finally realized why that recipe likes to fail. The lye is just too damned strong. Unless you adjust the procedure somehow, it can't work properly.
 
No, it doesn't grain out. Graining is driven by concentration of salt or alkali in the water phase. The alkali concentration in the lye heavy Castile recipe is only about 15% at its highest. That lye concentration is not nearly enough to make soap insoluble in the water layer, especially since the lye concentration is dropping in the water phase in response to the ongoing saponification reaction.

The real issue is that the emulsion created by stick blending that much water with a relatively small amount of fat is highly unstable.
 
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No, it doesn't grain out. Graining is driven by concentration of salt or alkali in the water phase. The alkali concentration in the lye heavy Castile recipe is only about 15% at its highest. That lye concentration is not nearly enough to make soap insoluble in the water layer, especially since the lye concentration is dropping in the water phase in response to the ongoing saponification reaction.

The real issue is that the emulsion created by stick blending that much water with a relatively small amount of fat is highly unstable.

Either hypothesis could be right, or they could both be somehow, in the absence of experiments to prove them.

One of the effects I watched with my own eyes was the soap graining out as it formed, much as in the early stage of HP but not as dramatic because no heat. I stirred for a real long time without blending to see what would happen. Hours. I saw flakes of soap forming gradually and floating around at the top, but the solution underneath stayed crystal clear -- so I'm pretty convinced of what I was looking at. And the process just locked up.

The boiled soap makers always started with a weak lye -- 15% at most, because more would inhibit saponication. I guess it's more liable to be a problem at the beginning. If the soap in this recipe dissolved in the water as the process proceeded, I think it would work with time, as suggested by the pictures and description.

What kind of emulsion is that anyway? Very weird. It must be water in oil, because you can put a glob of the stick blended stuff in water and it just keeps its shape and sits at the bottom of the bowl.
 
Reporting on my impressions of using this soap at 6 months cure with a comparison to 15-month cured Castile.

In any case, I do believe that even if some say you can use a Dual Lye Castile earlier (at 4-6 weeks), I would NOT recommend it. Even at 6 months, it's not anywhere near as mild as it should be in my opinion.

Hi Earlene thank you for posting your results.
Have you compared this KOH additive to salt or vinegar?
 
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Hi Earlene thank you for posting your results.
Have you compared this KOH additive to salt or vinegar?


So far, no, not in Castile soap. That is a plan, however.

I am joining the 'annual New Year Castile Soap Project' and will make them then. Probably tomorrow or the next day.

I have been using vinegar in soap for a couple of months, though not in a pure olive oil soap. I've only made 3 batches total of Castile soap so far. None had added salt. I have to develop my plan of how many & what size batches for this project, as well as what additives to include in each batch, so the exact recipes.

Thanks for asking.
 
So far, no, not in Castile soap. That is a plan, however.

I am joining the 'annual New Year Castile Soap Project' and will make them then. Probably tomorrow or the next day.

I have been using vinegar in soap for a couple of months, though not in a pure olive oil soap. I've only made 3 batches total of Castile soap so far. None had added salt. I have to develop my plan of how many & what size batches for this project, as well as what additives to include in each batch, so the exact recipes.

Thanks for asking.

The other important thing when testing Castile is how long the bar lasts with use. If it goes mushy half way through then I consider it a fail.

After all this then there is the other variable - the water you use in the shower. I don't know if it makes a huge difference or not. I don't get a lot of "snott" on my long cure single lye Castile. I don't know if it's my perception, my OO, my cure time or my water. I have to get others to test my soaps to cut out some of these variables - perception and water.

I have just started doing the same tests as you with all my recipes. It is very interesting reading your reviews. Thank you.
 
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The other important thing when testing Castile is how long the bar lasts with use. If it goes mushy half way through then I consider it a fail.

After all this then there is the other variable - the water you use in the shower. I don't know if it makes a huge difference or not. I don't get a lot of "snott" on my long cure single lye Castile. I don't know if it's my perception, my OO, my cure time or my water. I have to get others to test my soaps to cut out some of these variables - perception and water.

I have just started doing the same tests as you with all my recipes. It is very interesting reading your reviews. Thank you.

Good points. I guess I have so many soaps that I simply cannot judge how long any one of them lasts in the shower! I alternate between this bar, then that bar, then another one because I want to try so many of them out, that none of them gets used exclusively from start to finish. My husband, however, uses one bar of soap and finishes it before he moves on to another. Maybe I should enlist him in that task - determining how long a Castile will last in the shower vs his usual coffee soap that he loves so much. And does it get mushy with use. But then, mine are probably too young for that as yet. Maybe in the future...

And water certainly does make a difference. We have a water softener and when it runs its weekly cycle the water is noticeably very soft that day in particular, softer than any other day of the week. It took me a long time to get used to softened water; at first I didn't think the soap was rinsing off my body at all and that was commercial soap, not hand-crafted soap.


It's funny how we think about how long a bar of soap lasts in the shower. I don't think I ever considered that in my life before. We just used the same bar of soap, and replaced it when it got too small. We always used the same bar of soap and never anything different unless the store didn't have our 'usual' in stock. My goodness things have changed since I started making soap.
 
To add an interesting twist to the ongoing debate about high oleic soaps, please see Auntie Clara's blog post http://auntieclaras.com/2016/08/soap-holiday-2016-edition/ about the various soaps she and her family used while on vacation in Italy this past season. The second soap she discusses in the blog is a bar of her 2 1/2 year old castile.

Here's a quote from this article that I found especially interesting:

"...I’m now beginning to see that the rather prohibitive size and shape of traditional olive oil soaps like Marseille and Aleppo blocks, is not just an inconvenient coincidence. Those soaps come in blocks specifically because you aren’t meant to twirl them in your hands, dip them in bath water or a shower stream and rub them over your body. You’re meant to stand the soap away from water, rub the block with a damp cloth or sponge and then use the cloth or sponge to work up a lather and rub your skin.

"Used that way a bar of olive oil soap will last a very long time – and you’ll probably get just as clean. Easily arranged at home perhaps, but not so convenient when travelling...."
 
Such an interesting point you bring up DeeAnna...which to me makes a lot of sense. Some of my soap fans say they can't believe how long my current soaps last; one friend had a bar at a sink for over a year. Another friend has a CP shamrock from March still going strong at his work sink.I'm imagining a block of soap in an arid environment like Aleppo kept from running water or allowed to dry out between usages anywhere with simply a damp cloth over it lasting one helluva long time...
 
Thank you, DeeAnna. I will check out her blogpost.

Coincidentally, some of my Castile soap I made this past week is in blocks like that. I thought I'd try it to see if I like the shape. The jury is still out, of course because I won't be using them for a year. :)
 
I used one of the pink ones in the tub yesterday. No sliminess noticed. It was hard as a rock going in, sank to the bottom when I dropped it in the tub of course, but I retrieved it and placed in back in the soap dish. At one year, this dual lye Castile is quite nice. Lathers beautifully.

Castile%20-%20Dual%20Lye%20-%20Pure%20Olive%20Oil%20-%20Ribbon%20Pour%20-%202016June27%20-%20cross%20cut.jpg


A surprise came when I turned on the whirlpool jets toward the end of the bath and got a thick layer of soapy bubbles forming on the top of the water. Granted, I had put in a tiny bath bomb at the end as well, but it had completely disipated before I turned on the jets, but I can't rule out the effect of that in the water. And I had also washed my hair at the very start and rinsed the shampoo out in the bath water. So the combo of all three probably played a part in the thick lathery bubbles that formed. But it was still a surprise. I've never got that many thick lathery bubbles in a whirl pool bath at the end of the bath using only a bath bomb; not even using only bubble bath. And I don't tend to sit around in a bath for a really long time either, so I haven't done this kind of thing very often.

In any case, I am happy with my dual lye Castile at one year. I do have to be careful when using this soap to set it to dry more than with some other soaps, however. I noticed this morning the underside is still wet and somewhat gooey where it didn't get enough air circulation to dry out. When I had it at the kitchen sink, I always stood it upright to dry out and didn't run into a problem with a gooey wet underside like after the tub bath, when I did not stand it fully upright.

So the take-away at this point is proper drying out between uses. But that's necessary with all soaps, anyway.
 

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