Diagnose this soap, please!

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mzimm

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I have this weird batch of 50% lard, 30% CO, 15% canola and 5 % castor oil soap, that I'm pretty sure I messed up somehow in the making. Symptoms are: very oily to the touch, somewhat soft after 6 weeks cure time, and worst of all, is very drying to the skin. Ph strips put it at between 8 and 9, and phenolphthalein test of a little bit dissolved in 50/50 water/alcohol yields very (VERY) pink. Not even sure it's the PT that's making the pink, as there was red Brazilian clay and some red mica in it for colorant, but I don't think I'm dealing with lye heavy. I grated it up today, planning to rebatch it, but don't really know what to do to it, or add it to, to improve it. Should I cook it? Add it to a more conditioning soap recipe? Just use the grated soap in laundry?
Would love to hear some suggestions.
 
Are you sure the "oiliness" is oil and not lye water seeping? It's possible that it is oil, but it is mixed with enough FO to be irritating to the skin. The fact that the soap is still soft makes me think it is not lye heavy.
 
Did you use a scent? I once used what I thought was Tea Tree essential oil (but it wasn't, it was scented oil and who knows what) that made a similar to your recipe batch go sticky and oily.
 
Ok, I've attached a snapshot of my recipe with notes, hopefully you can glean clues from it. Unfortunately, the soap is all grated now, and won't really tell you much from a picture of it.
I was trying to formulate a recipe for my SIL who has very hard well water. (He was also the farmer who gave me the pig fat to render ) If you'll check out my notes in the "additives" section of the soapcalc recipe, I was attempting to add borax to the lye water, but was having trouble, and had to strain out what didn't dissolve. This borax thing is the only thing that I can think of in my soap-making that day that might have caused the odd results.

Yes I've zap-tested it and it is "no-zap."

I used a blend of essential oils for 1/2 of the batch, and a blend of two FO's for the other half. Both halves behaves the same as far as the undesirable results.

To use the ph strips, I dissolved a little soap in distilled water before wetting the ph strip, so it's results should be valid.

To use the PT, I dissolved a little soap in 50/50 distilled water/alcohol, according to the info I got here: http://summerbeemeadow.com/content/phenolphthalein-ph-and-soap
Second try on the attachment----Let's get that recipe flipped so you can read it
Sorry, showing my age....here it is again
Oh yes, one more thing---I tend to go very easy on FO's and EO's. Although I didn't record it, I used only 1/2 oz per half batch.

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I added the borax because as a soap additive, it softens hard water, gives a really nice slip to the lather, and cuts down on the soap scum you especially get in hard water. Although I'm no chemist, I do believe it can be called an emulsifying agent, allowing the fats and oils to stay in contact with each other until full saponification takes place. In the Failor method of liquid soap, she uses it as a "buffering" agent after dilution, and I've never experienced a reaction to it in the liquid soap I make.
I would not be surprised, though, if I it turns out that the borax caused the problems I'm having with this cp soap.
If I hadn't added the clay and the mica, I think I'd just use it for laundry soap instead of trying to fix it.
 
I added the borax because as a soap additive, it softens hard water, gives a really nice slip to the lather, and cuts down on the soap scum you especially get in hard water. Although I'm no chemist, I do believe it can be called an emulsifying agent, allowing the fats and oils to stay in contact with each other until full saponification takes place. In the Failor method of liquid soap, she uses it as a "buffering" agent after dilution, and I've never experienced a reaction to it in the liquid soap I make.
I would not be surprised, though, if I it turns out that the borax caused the problems I'm having with this cp soap.
If I hadn't added the clay and the mica, I think I'd just use it for laundry soap instead of trying to fix it.

Borax is great in liquid soap, but with Failor it's an additive after the soap is made. Maybe it can do something useful in bar soap, but not if it uses up the caustic, so maybe HP would be the process to try it with.

I'm not really familiar with the chemistry of this because I've never considered it, but a Google search seems to indicate that borax reacts with sodium hydroxide to produce sodium metaborate. Maybe that's the problem.

To help with hard water and bar soap, the options we usually consider are chelators like sodium citrate and tetrasodium EDTA. Good recipes shouldn't really require an emulsifier/solvent to saponify properly and not separate, but there are some options there too such as castor oil.

So yes, I suspect the borax.
 
You don't need to do the other two tests if you zap test - even when done correctly they don't really give any meaningful information (phenolphthalein especially so) other than wasting your time and money.

When you first posted, I wondered if it was in fact really superfatted- so if I understand ToMH, the borax would have reacted with some of the lye, causing a larger lye discount than planned?
 
When you first posted, I wondered if it was in fact really superfatted- so if I understand ToMH, the borax would have reacted with some of the lye, causing a larger lye discount than planned?

I'm not particularly familiar with borates and what happens when you add borax up front in CP, but yes I think it turned into a big lye discount. Certainly fits the symptoms, as you noticed. The part of the borax that appeared to dissolve probably dissolved as sodium metaborate, which is very soluble and evidently doesn't saponify oils.

Borax is pretty nifty in liquid soap though, added at the end. It's a pH buffer but not an acid (it's alkaline, actually), so you can aim at 0% superfat without concern about missing the mark or about over-neutralizing and releasing free fatty acids from the soap. It also increases the solubility of soap in water markedly. You can add dilution water a little short of dissolving all the soap. Then you add some borax and the rest dissolves to create an extra thick liquid.

Some folks think that Failor is obsolete or something, but most people don't even have half the knowledge that's in her books.
 
Thank you all for the GREAT learning here! I am especially appreciative of the time you've invested to give me thoughtful responses.
As I understand it now, the oily feel of the soap is from the lye discount caused by the reaction of borax and NaH, and we're thinking that that reaction produced sodium metaborate. If so, then instead of the conditioning properties I might have expected from a highly super fatted soap, my skin is reacting to the sodium metaborate left behind.
Thank you TEG for the encouragement regarding the zap test. I hadn't given my tongue enough credit until now!
And thank you ToMH for the suggestions about the other chelates. I'll save the borax for its other properties in liquid soap in future.
For this batch, I'm thinking I may just dilute it in water and use it to wash my very dirty truck, lol.
 
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