Salting out soap questions

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After looking at too much old soap today, I’m almost ready to try the salting out method. I’ve read @DeeAnna ‘s Soapy Stuff page and the linked threads, watched the YT videos, and read @KimW ’s thread from last fall about crumbly salted out canola soap with the ensuing discussion of how different fat profiles affect the results. The resources have been super helpful, but I still have a few lingering questions.

The superfat in my soaps is typically in the range of 2-3%. I use sodium citrate (or edta in the past) as a chelator and don’t have any issues with soap scum in the showers despite having hard water. I’m wondering if I should go through the extra step of adding lye to neutralize the excess fat.

My recipe is lard rich, so I am expecting that I will get curds, not crumbles. I don’t recall reading any details about a method to get from soap curds to soap powder. Suggestions? (Or point me in the direction of a thread)

If I want to try molding some of the soap, how does that work? Do I just press the fresh curds into the mold?
 
Give me enough time and I will answer my own questions. ;) I found instructions on the Soapy Stuff website for making soap powder and adding essential oil. I think I should do the extra lye step in the salting out, especially since some of my soaps may have had a bit more oil added with colorants. Now all I need is some free time.
 
Consistency: I don't exactly get what you're aiming for. I have had more than once a “tipped over” salt-out that held a ton of salt crystals between a very soft and mushy soap curd, that went rock hard over a few weeks (like salt bars). I imagine these are easy to crush into a powder (though they'll contain a ton of salt). Other salt-out actions resulted in an agreeable, pliable lump that was easy to shape (somewhere between HP batter and soap dough; easily put into silicone moulds).
I've not nailed down what was the difference, I suspect it is how vigorous one whisks the solution just after adding the salt. Not entirely sure (darn, didn't take notes), but I think the best (smoothest, most HP-like) results were from batches I didn't stir at all, but let the boiling brine do all the work for me (steam bubbles kneading and circulating the semi-fluid soap mud. Let it boil briskly for several minutes, use a spatula only to assure nothing is burning at the bottom; if you have added enough salt, it won't.).
However, I wouldn't classify the outcomes of salting-out between “crumbles” and “curds”; for the former I suspect other mechanisms to play a role (not boiling?). But then, I haven't read through KimW's efforts (yet).

Fatty acid profile: High-lauric and high-oleic/linoleic recipes don't work too well; some palmitic/stearic acid is important, otherwise the cake won't solidify upon cooling, and you can't separate the soap from the brine/glyerol. In winter, I could put the pot outside. Lard-based recipes should pose zero issue here.

There is a layer of dirt/mud/something sticking at the bottom of the soap cake swimming in the pot. This is NOT WORTH dealing with. Scrape it off and discard it. You'll lose a few % soap (but keep in mind, if you hadn't salted-out, you'd maybe lost everything).

Pot size: At least triple the volume of the soap. You'll add quite some water, and you want to have enough headroom for a well-behaved overboil.

Multiple salting-out: Yes, it's fun and impressive how clean one can get a soap that looked like waste initially. However, multiple rounds of salting-out also means multiple risk of over-whisking (bad separation between brine and soap), more time, more salt.

Amount of salt: that's a difficult one. I have had second salting-out rounds where the brine that had been kept back in the solidified soap disc was enough to trigger separation without any additional salt, just by heat + a bit of water. Obviously, it should be no more salt than can dissolve in the water. Which can be tricky to estimate when you haven't tracked the amounts of everything™ (which is impossible anyway). Some salt will inevitably carry over into the final soap, but the average salt-out soap doesn't make the best salt bar.

Superfat: Kill it only if you are unsure about the “state” of the superfat (suspecting elevated DOS danger). Add some NaOH into the first dissolution water and let it react (similar to HP, give it some time). At the very end with the glycerol addition, you then can (should) add your favourite superfat. But in case you're unsure about rancidity, it might be just as fine to toss one or another of the input batches, before ending up with a unsightly end product.
You might consider adding soda ash instead of NaOH to the brine. It'll neutralise free fatty acids (DOS precursor?) without being too aggressive during the process itself, as well as in the finished soap (you don't want to have pockets of NaOH lye in there!). In fact, if it weren't an irritant by itself, sodium carbonate would make even a better salting-out agent than sodium chloride (Hofmeister series).

Finish: Somehow you'll have to turn the cake into whatever shape you want your soap to have. Raw material on the softer side is pliable at room temperature, otherwise the way is open up to (oven or stovetop) rebatch-alike. However, I noticed that at elevated heat, young rebatch soap tends to “sweat out” excess brine from hidden pockets – which doesn't have to be a bad thing, but can be undecorative.
You'll have to replace the lost glycerol. You might now also want to add EO/FO/colourants/botanicals/exfoliants. Citrate/gluconate/EDTA. ROE. Superfat.

Cure time: At least with my trials, salted-out soaps need a substantially longer time than CP or HP to become hard enough to not instantly dissolve in water. One batch was still too soft after two months, another just barely usable. I wish you best luck that yours hardens up to your expectations in a decent time!
 
I fiddled around with salting out soap using a batch of accelerated lard-based soap that was originally made with a discoloring FO (coconut) as well as brown and blue mica. After two rounds of salting out I decided it would be a waste of water and salt to try to get it to a color that I would find acceptable for laundry powder. At that point, I threw it all into a large crock pot, melted it again, added glycerin, sodium citrate, black and grey mica, AC, and some salt. What I ended up with looked and behaved like damp fine sand, perhaps because of the salt addition (?). Yesterday I added 450 g of it to a batch of the same recipe (450 g of oils) with the SF set higher to account for the lack of SF in the salted out rebatch. Today I have a non-zappy bar of soap that was easy to cut. Yes, it looks like poured cement, but it smells like lime and a small end piece makes a perfectly acceptable lather.

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I'm not entirely sure what your goal(s) were, but it sounds as if you're reasonably happy with the results! Using salted-out soap as a partial rebatch stock is a good idea if the soap as salted out doesn't behave as intended. Which, honestly, surprises me. I'd have expected a high-lard recipe to be well-behaved.
I like it. It's sightly, but still you're probably out of danger that someone wouldn't use it because “too beautiful to use” 🤣.

Salting-out to get rid of colour isn't necessarily very efficient. Probably if it's (pure) pigments, but you have to expect that anything from artificially coloured micas, over discolouring FOs, to intrinsic colour of oily ingredients (annatto etc.) isn't exactly impressed by salting-out. Worth a try, but no guarantee. One of my salting-out batches had red palm oil in it, and the colour changed from a earthy ochre-salmon-olive to a decent orange during “decolourising”.

I threw it all into a large crock pot, melted it again, added glycerin, sodium citrate, black and grey mica, AC, and some salt. What I ended up with looked and behaved like damp fine sand, perhaps because of the salt addition (?).
I think so. It's approaching a salt bar in its composition, and these are rather on the brittle side too. I don't quite get why you added salt again? Even if you hadn't, there might be enough trapped between the soap curds to re-initiate separation. I haven't found the perfect ratios of soap/water and soap/salt yet either.

it looks like poured cement, but it smells like lime
Well, that's the whole point of cement to consist of two thirds (quick)lime 😜.
(I'm still struggling with the metaphorical potential of the homonym between that whitish scum in my kettle, and the citrus juice that I use to etch it away.)
 
I'd have expected a high-lard recipe to be well-behaved.

The salted out soap was well enough behaved. I’m sure I could have gone in the usual direction with it, but it didn’t seem worth the effort due to the color.

It's approaching a salt bar in its composition, and these are rather on the brittle side too. I don't quite get why you added salt again? Even if you hadn't, there might be enough trapped between the soap curds to re-initiate separation. I haven't found the perfect ratios of soap/water and soap/salt yet either.

The extra salt went in on a bit of a whim. The consistency change after the first addition was interesting so, mostly out of curiosity, I kept adding salt a little at a time. I recently watched a YT where the maker added powdered soap to a new batch. When it got to the wet sand stage, I saw the potential and kept stirring until it was just damp.

I’m going to pretend that I was clever enough to use the lime FO intentionally in my cement soap. ;)
 
Reviving this thread to say I salted out some soap ends and shavings last week, it worked pretty well even though it ended up a not very attractive gray. I decided to make it into laundry soap and mixed it 50/50 with washing soda per @DeeAnna ’s recommendation. The happy surprise was that it worked amazingly well! I had a gardening shirt that was not suitable for public viewing and I was shocked to see that it came out looking, well, not NEW but reasonably white. Also, it really isn’t that hard to do. I used a tall pot so the soap and brine could boil without worrying about boiling over.

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New car FO, earthworm/compost FO, concrete FO. The world is crazing out. I wonder what is coming next. Underarm perspiration FO?
Their's an element of truth in your statement above, in the "perfume industry" when designing a signature scent its gotta have an element of "not so desired scent" stinky if you will 🤣💫.
 

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