Dilution issue

[peace-love-and-suds]

I am trying to figure out the math behind the dilution rates. I do not understand why in Catherine Failor's book she indicates that

15% actual soap = 3:1 ratio water/paste

In my mind this is diluted to 25%.


Also, when I cook my liquid soap, I like to start with a little more water than needed to make dilution easier (with a certain formula). I cook the water out and weigh the pot to find out how much water loss I've had. The problem is I do not know the equation to get the percentage of paste per water.

If I start with 30% dilution (16oz water to 16oz paste) and I weigh the pot after a while and have only 13.5oz of water left, how can I get the percentage actual soap? I know it would be somewhere between 30% - 35%. The equation does not seem to be linear.

 

[peace-love-and-suds]

btw, I've scanned through previous posts for about an hour and did numerous google searches but can't seem to find the math behind all of this. What I HAVE seen is a lot of people don't agree with Failor's calculations. I just want to know what she was thinking.

 

[peace-love-and-suds]

I forgot to ask... I saw that one user dilutes her soap in a canning jar with the lid on. Wouldn't the steam from the water loss cause the jar to explode under pressure?

 

[seven]

i don't think there's an exact formula for this. all i know that it's better to start with less water and add more as you go along. i personally like to start with 1:1 (1 part paste: 1 part water).

 

[Susie]

I never could make sense of Catherine Failor(or anyone else's) dilution rates. But then again, I am horrible in math. If it is a new recipe to me, I start with a 0.5:1 ratio of water to paste. That way, I know I am adding more always. I do record how much water is required on each batch page, so if I am making the recipe a second time, I just add the whole amount at once.

 

[new12soap]

Okay, I can't speak for Failor, but just taking a stab at it... Yes, a 3:1 ratio of water to paste is 25% paste. Is she possibly calculating actual soap, not the water that suspends it into the paste? In other words, is paste 60% actual soap? That is also the only thing that comes to mind when reading your 16oz paste plus 16oz water = 30% dilution (???)

One other possibility is that it's a misprint, an error.

Just curious, is there any particular reason you want the percentage of actual soap?

 

[peace-love-and-suds]

Okay, I can't speak for Failor, but just taking a stab at it... Yes, a 3:1 ratio of water to paste is 25% paste. Is she possibly calculating actual soap, not the water that suspends it into the paste? In other words, is paste 60% actual soap? That is also the only thing that comes to mind when reading your 16oz paste plus 16oz water = 30% dilution (???)

One other possibility is that it's a misprint, an error.

Just curious, is there any particular reason you want the percentage of actual soap?

I'm just a nut like that and HAVE to understand everything. Outside of that I've been writing a very complex excel workbook for a couple of years now that deals with every aspect of a soap business all the way down to auto calculation of taxes. I need the equation to program it in to the workbook. I figured since most people in the community reference Failor's method, her dilution table has become an "industry standard" so I thought I better go along with it. If she is counting the water in the paste then those calculations would also be off because the paste will cook different amounts of water out depending on the cook time, temp, and other confounding variables. It kills me she didn't include her math.

 

[Susie]

I figured since most people in the community reference Failor's method, her dilution table has become an "industry standard" so I thought I better go along with it.

While I do not sell my soap, and I have not been making liquid soap forever, I think I can safely say that many people no longer use any of her methods any longer. Not saying all, not saying most. Just saying many. Matter of fact, if you look around this forum, there are many posts showing easier, faster ways of making liquid soap. After all, saying that she is the industry standard would be like the automobile industry still making cars exactly like Henry Ford. We've come a long way since then.

I use this lye calculator for my liquid soap. It uses a higher amount of water to make the soap with. I find that gives me better results. And I ignore all the borax and stuff. No need to neutralize if you don't make lye heavy soap. I don't use their dilution rates, though.

http://summerbeemeadow.com/content/advanced-calculator-solid-cream-or-liquid-soaps

 

[peace-love-and-suds]

While I do not sell my soap, and I have not been making liquid soap forever, I think I can safely say that many people no longer use any of her methods any longer. Not saying all, not saying most. Just saying many. Matter of fact, if you look around this forum, there are many posts showing easier, faster ways of making liquid soap. After all, saying that she is the industry standard would be like the automobile industry still making cars exactly like Henry Ford. We've come a long way since then.

I use this lye calculator for my liquid soap. It uses a higher amount of water to make the soap with. I find that gives me better results. And I ignore all the borax and stuff. No need to neutralize if you don't make lye heavy soap. I don't use their dilution rates, though.

http://summerbeemeadow.com/content/advanced-calculator-solid-cream-or-liquid-soaps

I saw IrishLass's post regarding her method of LS making. I wonder if her method (thus my question about the canning jar exploding from internal pressure) would apply when using water instead of glycerin?

http://www.soapmakingforum.com/showthread.php?t=46114

 

[peace-love-and-suds]

I'm still a little weary about the paste producing itself just by sitting without a heat source throughout the entire duration.

 

[DeeAnna]

"...Is she possibly calculating actual soap, not the water that suspends it into the paste?..."

Yes, I think she's figuring her dilutions on a pure soap basis, and most of us dilute on the paste weight. It probably isn't a big deal either way when diluting a soap high in unsaturated fats (olive oil, for example) that is forgiving about dilution. Her method might give better results, however, when figuring the dilution of a soap high in short-chain saturated fats (coconut oil) that is much more sensitive to dilution.