Another question about Lye amount

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Kathymzr

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Would someone explain, as to a child , about what are the consequences of different lye amounts. I made a soap, for example, with lye:water at 2.5:1, and some at 33%. How does the lye amount affect the product? Does less water matter? Are there cases where less or more water is needed? Seems less water is less to evaporate. I am blasting my soaps with a fan to combat humidity and it seems to be working. Thank you if someone can clarify!
 
What you're talking about is changing the amount of water, not the amount of alkali (NaOH). If you nail down the weights of the fats, and you nail down the superfat percentage, the NaOH weight is going to be constant. It won't change.

Once the fat weights and lye weight is set, the next thing to set is the water weight. You change that by changing the "water as % of oils" (which I recommend not using), or the "lye concentration" or the "water:lye ratio". These settings do not change the lye (NaOH) weight. Whichever one you use will only change the WATER weight.

A useful "when in doubt" water content is 33% lye concentration or 2:1 water:lye ratio. They both mean approximately the same thing, and this amount of water works well for many soap recipes.

"...Seems less water is less to evaporate. I am blasting my soaps with a fan..."

You seem to be focusing on the water after the soap is made. But the amount of water also affects the soap when you make it.

Less water reduces the chance of emulsion failure and separation in the mold. It definitely reduces the chance of getting "glycerin rivers". It may reduce some types of ash on the finished soap according to some soapers (I am not able to confirm this).

Less water reduces the chance the soap will go into gel, especially if the lye concentration is 33% or higher. It can reduce the working time -- the time you have to work with the batter before it gets too thick to stir. It can speed up slow moving recipes (example: 100% olive oil soap) -- a useful thing. It can also speed up recipes that move fast (ex: 100% coconut oil soap) -- not necessarily a good thing.

Less water reduces the % of water in the finished soap. It doesn't necessarily reduce the cure time, since curing includes the time needed for chemical and physical changes in the soap molecules as well as for reducing the water content.
 
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Every morning I settle with my coffee to learn soaping—So fun to follow activities! It helps a lot to clarify these things, even if again! Thank you! Makes sense. What water:lye ratio do you use? And is there any real reason to change it?
 
Less water also is reduces the chances of warping... In case you decide to HP..

Nothing to add. Not after DeeAnna lol

But I will add, after studying her notes on water..... In general I use less if majority of my recipe is soft oils, slightly more but not too much if I'm using more hard oils. Otherwise I use 2:1, even in HP.
 
Also, why do some people swear by 33% water/oils? Seems that if lye is a constant based on saponification values, that water:lye is more precise, although I guess working time would be something to consider depending on design. Am I thinking clearly on this? I ask because I finally got the batter right with reasonable working time at 2.5:1 ratio. 3:1, then, could maybe give (theoretically) more working time?
 
Because 33% seems to be the sweet spot. It gives enough time to swirl, recipe dependent will still gel if insulated if in a warm room. I force most soaps to gel but that is another question to research. Higher water causes faster gel and in some recipes overheating leading to volcanos. As DeeAnna mentioned it also leads to glycerin rivers or crackling with is most evident in soap with TD added. I use a 30-31% Lye Concentration which approx 2.3:1 ratio.

3:1 is approx 37.8 water as percent of oil or a 25% Lye Concentration. That is the amount of water that can cause emulsion problems with high OO batters and will readily overheat it not watched.

Some here will state that higher, above 33%, lye concentration will give more work time. I have never found that to be true at least not for my high palm recipes.
 
I have started using 38% lye concentration. So far this is working well for me. Would this be considered too high for most? I do not normally gel soap. I use what I think is a balanced formula (32 % palm, coconut, and Olive, 4 % castor).
 
I have started using 38% lye concentration. So far this is working well for me. Would this be considered too high for most? I do not normally gel soap. I use what I think is a balanced formula (32 % palm, coconut, and Olive, 4 % castor).
If it works well for you, I wouldn't worry about what others use. How each person soaps is such a personal preference, that it really doesn't matter what others are doing.
 
I have started using 38% lye concentration. So far this is working well for me. Would this be considered too high for most? I do not normally gel soap. I use what I think is a balanced formula (32 % palm, coconut, and Olive, 4 % castor).
Are you using 38% Water as Percent of Oils? That is around 27% Lye Concentration which many consider full water.
 
When you say 38% lye concentration I am assuming that you calculated that by lye divided by lye + water? I normally use 33% (lye of 200 divided by 600 (lye 200 + water 400).

38% would be too high a lye solution % for me with some floral fragrances and ocean fragrances that accelerate. Also may be too high for me with some soaps with a lot of complicated swirls. I want more time with a fluid soap batter. Would work for me on many simpler designed soaps and non-accelerating fragrances. I adjust water depending on fragrance and design although I am mostly comfortable with a 33% lye solution for most of my soaps.
 
38% Lye Concentration would be too high for some recipes if you want to do intricate swirls. It really depends on your goals with that particular soap. In my limited experience, I have done 40% Lye Concentration and it works fine for my fairly plain Castile soaps. But when I want to do intricate swirls or need a lot of time between mixing up the batter and completing the design (due to separating the batter, adding multiple colorants, building the design, etc.) I use a 33% Lye Concentration. But the actual recipe also plays a part in how much time I will have to work.
 

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