No superfat

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Please correct me if I'm wrong (as I know you will...lol). I can make a gentle bar of soap with 0 SF, if formulated, measured, and cured correctly.
lol, I'm sure the more experienced people will give better answers, but I had to chime in anyway.
I thought the SF was really more to ensure the lye had all been used up more than to actually increase moisture or make a bar more gentle. So, if that is correct a 1% or so SF would actually give a better chance of getting a gentler bar of soap. Depending on formulation, which oils etc.
But, that's just my newbie opinion of course. :)
 
lol, I'm sure the more experienced people will give better answers, but I had to chime in anyway.
I thought the SF was really more to ensure the lye had all been used up more than to actually increase moisture or make a bar more gentle. So, if that is correct a 1% or so SF would actually give a better chance of getting a gentler bar of soap. Depending on formulation, which oils etc.
But, that's just my newbie opinion of course. :)
Yes, I think traditionally that was the purpose of SF. It seems that many people have it in their head that SF makes their soap moisturizing. I don't agree at all as I don't think soap is or was intended to be moisturizing. Less stripping, yes, but moisturizing, no. I had an experienced soaper tell someone that superfatting under 5 was dangerous. I disagreed and even gave examples of people using 0 SF. I read on here that Kevin Dunn tested with a negative SF and the soap was not lye heavy. She wouldn't even hear it. Agreed to disagree.
 
Yeah, I'm not surprised. Based on all the research I've done in the last 8 months or so there is a lot of bad info floating around and a lot of people believing what they see/hear. I've seen some bad info passed on here as well, although it's rare and they are usually corrected real quick. :)

I think the 5% is probably a number someone decided was a good percentage to keep newbies out of trouble. :)
 
I would think that you could. But why wouldn't you want some wiggle room when it comes to lye concentration/saponification?
Maybe not wanting free floating oils for one. I'm not saying that I SF at zero, but I know people have and still produce a usable bar of soap. She is plain out saying that under 5 will damage your skin. From the reading that I've done, even SF at 0 most likely has some sort of SF due to most lye not being 100% pure.
 
She is plain out saying that under 5 will damage your skin. From the reading that I've done, even SF at 0 most likely has some sort of SF due to most lye not being 100% pure.
Who is this She you speak of?
I am guessing that She thinks that some lye may not saponify if you go under 5% and therefore there would be lye pockets in the soap?
I have soaped at 1% and liked the soap, with no ill effects.
 
Who is this She you speak of?
I am guessing that She thinks that some lye may not saponify if you go under 5% and therefore there would be lye pockets in the soap?
I have soaped at 1% and liked the soap, with no ill effects.
Just another soaper from another forum. She's very active and gives answers/advice regularly. I guess that's why I assume she's an experienced soaper. Ya know what happenens to those who assume??? Who knows. She may even be on here. Although, if she were, I think she would know that's not true. I don't say much and when I do, it's just to genuinely try to help or offer some information maybe the OP did not know. It just frustrated me for some reason and I needed to vent. Thank you all for letting me do just that ;)
 
I make gentle soap and superfat from 1-2% only higher with salt bars. I want as little free oil going down my drains as possible. I have soaped in the negative 1-3% range with no problems. But it has been found when soaping in higher negative numbers it takes more water/liquid and longer cure times to become zap free soap.
 
I make gentle soap and superfat from 1-2% only higher with salt bars. I want as little free oil going down my drains as possible. I have soaped in the negative 1-3% range with no problems. But it has been found when soaping in higher negative numbers it takes more water/liquid and longer cure times to become zap free soap.
What would be the reason to soap with a negative SF? I know it has been done but I don't recall why it was done. Is it done for the purpose of drains and oils?
 
Read through this thread. -30% super fat.

I keep meaning to try the recipe but haven’t had the time. The thread is super long mostly due to a discussion of method, if I remember right it cured to a basic Castile
 
If you don't adjust your recipes to account for the actual NaOH purity, there's a "hidden" superfat built into every bar soap recipe. This hidden superfat is in addition to the superfat setting you choose.

For example, my NaOH is 96% pure. If I use soapcalc or any other online recipe calc, these calcs assume the purity is 100%. The difference between the assumed 100% and the real 96% is 4%.

If I type 5% into the superfat (aka lye discount) setting in soapcalc, the total superfat is = 5% + 4% = 9%. (Assuming the saponification values are perfectly accurate.*)

If I set the superfat to 0% and use this same NaOH, the actual superfat would be around 4%.

But even if your soap ends up a little lye heavy -- something like -1% to maybe -3% -- this is honestly not the kiss of death. A small amount of excess alkali will dissipate during the cure time and the soap will be fine in the end. The alkali reacts with the carbon dioxide in air and converts to sodium carbonate (washing soda). That's the white "ash" we all love to hate on our soap. Just give it time.

If your soap is really, really lye heavy and you use a typical amount of water in the soap, however, the excess lye probably won't dissipate in a reasonable amount of time.

* I use a spreadsheet to calculate my recipes, and I set the calculations up to account for the NaOH purity. My normal superfat is 2-3% for almost all of my recipes and unless something goes haywire, this soap is never zappy. I have set the superfat down to 0% for making laundry soap, and I can tell this soap is slightly zappy when done. That tells me my calculations and sap values are pretty accurate.
 
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From my personal experience, I could tell no difference between adding 10% SF and not. Did tests on both Shea and Cocoa butters. I didn't feel any difference. Maybe you need super sensitive skin or something to make out the difference. I think its more psychological and more for marketing / labelling purposes than to actually get the intended purpose of the butters for the skin. Its also possible that it could have long term effects / benefits. Maybe someone who used SF soap regularly and made the switch suddenly to non SF might notice something different.

Meh... its all a conspiracy I tell you :eek:
 
Read through this thread. -30% super fat.

I keep meaning to try the recipe but haven’t had the time. The thread is super long mostly due to a discussion of method, if I remember right it cured to a basic Castile
This method only works with high water. I tried it with much less water and maybe a -30% superfat, after approx 2 years it still zapped.

Does anybody do it because that's just how they prefer their body soap? That you know of, of course.
I prefer not to wash with oil and my plumbing hates superfatted soaps.
 
I guess if I could superfat at 0% and reliably get a "no zap" result in my soap, I'd be okay with superfatting that low. As I said above, I know a slight lye excess will cure out, but personal preference wins here -- I prefer a lightly superfatted but "no zap" soap. Of late I'm choosing to superfat at 2%.

Apparently a typical practice in modern commercial soap making is to use very little superfat (under 1%) to zero superfat.
 

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