Water discount

[Plschrader]

one more time.......because I am thick skulled. IF I choose to water discount........I run my recipe through the lye calculator of my choice...........then, by hand, calculate the discount. I can’t make an adjustment in the calculator for the water discount like I can with superfat?

Who water discounts and why?

 

[steffamarie]

You can account for a "water discount" in the calculator usually. I use SoapCalc and SoapMakingFriend and they both allow it. For example, I usually prefer to soap at 33% lye concentration. If I want to use less water to help my bars firm up faster, I'll use a higher concentration of lye. The lye amount remains the same since it's what's necessary to make soap, but the water amount will decrease. This makes my percent concentration higher since there's less water. Does that make sense? In this situation, I'll choose 40% lye concentration. Then the calculator does all the work letting me know exactly how much liquid I'll need to add to the lye to achieve this concentration. It'll be less water than I would need for 33%.

I hope that all makes sense. It can certainly be confusing to learn.

 

[Plschrader]

Thank you. The whole topic is confusing.

 

[steffamarie]

Especially because people like to talk about water discounts as "10% water discount". This doesn't make any sense at all to me and I prefer to ignore that whole concept and think of things in terms of concentration instead.

 

[DeeAnna]

I agree with Steffamarie. Water discount, full water, and "water as % of fat" are concepts are widely taught in the handcrafted soap making world, but don't really have any scientific basis or consistent meaning. Use either lye concentration or water:lye ratio, and you'll be happier in the long run.

If you start using lye concentration or water:lye ratio and ignore the myths of "water as % of oils" and "full water" and "water discount", you will learn that tweaking the water content a little higher or a little lower is just a normal adjustment to make, not something to be scared of or confused by.

From my website, here's a quick 'n dirty table: https://classicbells.com/soap/waterRatioConc.asp
And here's my article with more detail: https://classicbells.com/soap/waterInSoap.asp

 

[Iluminameluna]

I don't masterbatch because I've no place to store the mixed lye. A small jar of lye is easier to put away.
However, I do this when I'm going to soap with added liquids or just water-containing additives:
Do the calculation for 2:1 lye to water ratio. Note how many grams of liquid that means. Also note how much lye I'll need.
When I'm going to actually soap, I measure out equal amounts of lye AND water, then measure the extra ingredients I'll be adding, such as honey, liquid milk, frozen fruit, frozen veggies, etc.
This way, I know exactly how much liquid I'm going to need, besides water, and that I won't need as much cure time than if I did the extra amount of liquid ingredients plus the whole amount of water in the recipe.
So, if you're wanting to dissolve the lye first, and cool it, THEN add watery additives that might contain sugars, this way they don't scorch and you don't need ice cubes (not practical for me).
I hope this helps.

 

[KiwiMoose]

one more time.......because I am thick skulled. IF I choose to water discount........I run my recipe through the lye calculator of my choice...........then, by hand, calculate the discount. I can’t make an adjustment in the calculator for the water discount like I can with superfat?

Who water discounts and why?

I totally get ya! Just when I have this one clear in my head, I go and forget it again. I think it's my menopausal brain not working correctly.

Essentially, I don't even know how much water I have in my recipes - to answer your question I had to go back and look at a few recipes to compare. The reason I don't know is because I don't use any of the water settings in my calculators. I only use the lye concentration setting. I lower it to 28% if I am doing swirly things and increase it to 30 -33% for other recipes.

More water means a greater likelihood of the soap gelling, and also greater shrinkage during cure. And I think it can also be more likely to get soda ash.

My best comparison is when I made a ghost swirl soap - where part of the soap gelled and the other part didn't. I must reiterate, I did not calculate anything to do with water for this - all i did was alter the LYE concentration from 28% ( for the gelled part) to 45% (for the non-gelled part). This resulted in a change of water:lye ratio from 2.57:1 for the (28% lye conc.) to 1.22:1 ( for the 45% lye conc.)

I wish i could give you a clearer explanation but it really does do my head in thinking about it - so i can completely empathise.

 

[Obsidian]

I personally hate the term water discount and concentrations confuse the heck out of me.
I know the higher the lye concentration, the less water is being used but I can't move past thinking it also means more lye. Bigger numbers=more and my brain just can't accept otherwise.

I've choose to use ratios, 2 parts water to 1 part lye. This works for all my recipes and give nice consistent results and I don't have to break my brain looking at numbers lol.

The only time I would alter this ratio is HP, then its 3:1

 

[DeeAnna]

"...I've choose to use ratios ... and I don't have to break my brain looking at numbers lol...."

Yep, this is exactly what I suggest to people who think like you do.

Water:lye ratio focuses on the water in the lye solution. As the water:lye ratio gets bigger, there's more water to dilute the alkali.

Lye concentration is focusing on the alkali (NaOH, KOH) in the lye solution. The bigger number for lye conc, there's less water to dilute the alkali.

Whichever one your brain likes best is the one to use -- water:lye ratio or lye concentration. They're talking about the exact same thing, they just look different.

 

[KiwiMoose]

I personally hate the term water discount and concentrations confuse the heck out of me.
I know the higher the lye concentration, the less water is being used but I can't move past thinking it also means more lye. Bigger numbers=more and my brain just can't accept otherwise.

I've choose to use ratios, 2 parts water to 1 part lye. This works for all my recipes and give nice consistent results and I don't have to break my brain looking at numbers lol.

The only time I would alter this ratio is HP, then its 3:1

I'm so pleased that you also get confused by this @Obsidian. I look up to you as an experienced soaper, so to have you on board with this confusion makes me feel so much better

 

[pmalin]

The whole topic didnt make sense to me either. If I chose calculate everything manually, what would be my total amount of water, then I could choose to discount it based on the understood full amount. Well nothing seemed to explain it so I eventually just started using
a ratio of water to lye where my water is 2.35 times the mass of the lye. It seems to be discounted enough but works well for me. Now I see others are talking about using a ratio and I am glad to see this discussion.

 

[DeeAnna]

"...then I could choose to discount it based on the understood full amount..."

That's one of the problems -- what is the definition of "the full amount" of water? And why is this truly useful and important? There isn't any consensus.

"...I eventually just started using a ratio of water to lye where my water is 2.35 times the mass of the lye..."

A ratio of 1 part lye to 2.35 parts water is a lye concentration of 29%. That's about what many people call "full water."

As a person with a fair bit of chemistry training and work experience (I'm a chemical engineer and have worked as a chemistry lab tech), the idea of "discounting" from some "full water" standard make utterly no sense from a chemistry point of view. I really don't see the point of this, and I have no idea how it all got started.

But then there are other ideas embedded in the handcrafted soap making culture that don't make sense either. But they're here to stay, I guess, and we'll just have to deal with that.

 

[pmalin]

Thanks for the reply DeeAnna, that is helpful information.

 

[Richard Perrine]

If I am reading DeeAnna's post correctly, I agree with her. I almost NEVER following the soap-calc's recommended amount of water to be used. 99% of the time, I use as much water as there is lye...that's it and it's been smooth sailing. Water is only there to dissolve the lye and create a solution medium for the saponification process to occur efficiently, nothing more.

 

[Plschrader]

If I am reading DeeAnna's post correctly, I agree with her. I almost NEVER following the soap-calc's recommended amount of water to be used. 99% of the time, I use as much water as there is lye...that's it and it's been smooth sailing. Water is only there to dissolve the lye and create a solution medium for the saponification process to occur efficiently, nothing more.

Interesting

 

[Richard Perrine]

I started last summer and don't know better in some cases. I quickly wondered what the volume of the water was all about and ignored it as soon as I discovered it didn't make any difference for me.