Using Water Discounts & Curing Time

[TeriDk]

"...If using less water does nothing for shortening the cure time, I'm not seeing a benefit..."

Really? I've spent a fair amount of time trying to educate folks about the benefits of using less water and about the use of the lye concentration setting, rather than blindly using that "38% water as % of oils" setting. Here are some pros/cons that will hopefully change your mind on this matter --

Less water => harder soap at the time of unmolding so you can unmold and cut sooner, faster rate of saponification which is good for recipes high in unsaturated fats (castile being the prime example), less chance of emulsion failure (separation) in the mold, less likely to go into gel, max temperature during saponification is higher, less likely to show streaking or mottling (aka glycerin rivers).

More water => slower rate of saponification which is good for recipes high in lauric and myristic acids (100% coconut oil being the prime example) and for accelerating fragrances, slower to come to trace (fancy decorative swirls and such), max temperature during saponification is lower, more likely for the soap to go into full gel on its own.

As you become familiar with your go-to recipes, you'll figure out what basic lye concentration works best for your soaping style. Once you find that sweet spot, then you can deliberately vary the lye concentration to get the soap to behave differently for various recipes, decorative techniques, accelerating fragrances, and different additives.

ETA: The "water as % of oils" number can be correlated to the lye concentration and water:lye ratio ONLY for recipes that have the same average saponification value. If you change the fats in the recipe, the relationship between "water as % of oils" and the other two will also change.

For an introduction to using lye concentration rather than "water as % of oils", please see this thread:
http://www.soapmakingforum.com/showthread.php?t=54095

...and read the full explanation here:
http://www.soapmakingforum.com/showthread.php?t=53642

Thanks, I will review these links. The snowflake bar did unmold nicely and is a decorative hand soap only.

 

[TeresaT]

DeeAnna: It makes total sense to me. The less water you use, the stronger the lye solution will be, the quicker the oils will saponify and the harder it will be (immediately) because there's less water to make it soft. That's why I soap at 33.333% solution, that's my "sweet spot" as far as controlling my oils is concerned. Any stronger and I'm plopping into the mold. Any weaker and I'm spilling the batter all over the place. Of course, I could learn to control my SBing better...

 

[mymy]

TeresaT : Yes, I think 33% is an ideal concentration. I tried 29 and 30, the batter hardened quite fast.

 

[DeeAnna]

If you mean 29% to 30% lye concentration, Mymy, then your soap should trace slower, not faster at 29-30%, all other things being equal. The lower the number for lye concentration, the more water there is in your batch.

I use 30% to 31% lye concentration when I want to try any fancy work or if I'm using a fragrance that accelerates. I also see more tendency to streaking and mottling in the soap (aka "glycerin" rivers) with these lye concentrations, however.

I use 33% lye concentration if I'm making a basic soap and I don't need the extra time to play.

 

[TeriDk]

Deanna - Bless your heart. I did read these threads and it was based on these threads that I decided to try a higher lye concentration - I will try to do a better job of using the correct terminology. Better yet I found the link to shorter curing time (rivercitysoaps.com/dwcp.pdf). I think I'm more happy that my memory served me...go brain!

I have a better understanding of the benefits. Now the other part of my original question is if you use 1/2 water + 1/2 milk (added to oils) for your liquid amount, would having a higher lye concentration work?

 

[mymy]

Dee : Yes, you're right! I'm so tired till I couldn't think straight.

 

[DeeAnna]

Teri -- Would it work? It sure can, but here are some ideas to consider before you soap --

If you want to put the max amount of fluid milk into your recipe, it seems obvious that you should soap with more liquid (28% lye concentration) rather than less (30% or whatever).

Problem with 28% lye concentration is the higher risk that the soap will go into gel with more liquid in the batter. If you don't mind if the soap gels, then that's no problem, but a lot of soapers want to avoid gel to keep the soap light colored. So if you soap with 28% concentration, the plan should be to keep the soap as cool as possible during saponification.

If you want to soap with less water but want to get as much fluid milk as possible into the batch, one thing to consider is to not split the liquid into half water and half milk. Instead, use just enough water to make a 50% lye solution and use fluid milk for the balance of the liquid needed. That will put the max fluid milk into the batch -- and you can use this method even with 28% lye concentration.

Another technique is to add powdered milk to the fluid milk. This will increase the amount of milk solids in the batch. I usually add enough extra powdered milk to the fluid milk to convert the water in my lye solution into fluid milk. Strain the milk solution before putting into your soap.

Hope this helps.

Mymy -- I'm pooped too! It's been a long day and I'm starting to make mistakes from fatigue. Good thing quitting time is near.