Free fatty acids from soap for making ointment

[natik]

I was searching how to make a birch tar ointment, which was widely used when I was growing up in Ukraine. In one of the tutorial, as a base, the lady used fatty acid extracted from the home made soap. She diluted grinded soap with tons of lemon juice, then washed resulted fat in water until it didn't taste sour, and then mixed it with the birch tar. Alone the way, she was explaining, that free fatty acids are really good for the skin. She didn't seem to care what oils were used to make the soap in a first place. What was important for her is that it is not regular fat. Although, at the end, she mentioned that if ointment is too thick, one can use oil to dilute it to the required consistency.
I am currently waiting for the birch tar to arrive and will try to make the ointment with the soap. It got me thinking though, does she make a good point? Maybe we all have to start making soap with whatever oils we like and then release fats by adding citric acid/lemon juice and what not? Is it really better?
I am not a very experiences soaper, all I know about fats and soaps I have learned on this forum. There are lots of very knowledgeable people here. I would like to know your opinion about it.

 

[DeeAnna]

"...Maybe we all have to start making soap with whatever oils we like and then release fats by adding citric acid/lemon juice..."

Bear in mind there are many, many types of fatty acids that have varying properties. At the very least, some fatty acids are liquid at room temp; others are solid. If you want to treat soap with acid to harvest the fatty acids for use in other products, I'd think you will want to pick the fats you use with some care. A random collection of fatty acids might not suit your purpose.

 

[Saponificarian]

And as a follow on to DeeAnna's post above, I believe a lot of the fatty acids that you want as free fatty acid in soap are available for purchase in their pure form now. If you are willing to splurge a little you can get them and experiment in percentages until you find what works, and could be replicated should you decide to make more.

 

[natik]

I have some 80% shea butter soap with 10% coconut and 10% castor oil, which is very hard and almost doesn't leather. Will try that one first.
The questing still stands is it really better to use free fatty acids rather than straight butters and oils? And why.

 

[natik]

And as a follow on to DeeAnna's post above, I believe a lot of the fatty acids that you want as free fatty acid in soap are available for purchase in their pure form now. If you are willing to splurge a little you can get them and experiment in percentages until you find what works, and could be replicated should you decide to make more.

I know that free fatty acids could be purchased, I have stearic acid in my cupboard. But theoretically, is it better to get less processed from soap?

 

[Saponificarian]

You want a straight Yes or No answer. Unfortunately, I can't tell you if it is better or not as I haven't made anything from free fatty acid from soap. Less or more processed is relative.

I would use fatty acid, be it from oil and butters or in their pure form because it can be measured, tracked and replicated. I don't see why I would go through the long process of extracting free fatty acid from soap to end up with a product with unknown fatty acid composition that can't be replicated every time. However, that is my opinion, you might feel differently.

 

[natik]

You want a straight Yes or No answer.

Soaping and lotion making is more of a fun hobby for me. I like experimenting, but also would be good to know the basis of why something is happening. I would like somebody explain the difference between free fatty acids vs oils/butters, is there any difference in skin absorption and benefits. As for being able to replicate again and again, that doesn't worry me much. I don't plan on selling it. And even if my first ointment will feel perfect, I will most likely make it differently next time, just because I can. Plus, they say that it is good to change creams and lotions so we can get all benefits from different oils.
Although, I don't do it with my soaps. I have finally figured out my perfect recipes and sticking to them for now.

 

[natik]

Ok. I think I found the answer.
This article https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8767382/ discusses the refining oils to free fatty acids. Seems like turning oils into soaps and then to fatty acids is a type of chemical refining, which removes such beneficial compounds like tocopherols and polyphenols. So no free fatty acids, virgin butters and oils still win.

 

[Mobjack Bay]

I would like somebody explain the difference between free fatty acids vs oils/butters, is there any difference in skin absorption and benefits.

Yes, there are differences in the way different fatty acids interact with skin, and differences in the way single/free fatty acids versus triglycerides interact with the skin. Long chain saturated fatty acids more or less sit on the skin as a barrier while an unsaturated fatty acid, like oleic acid, may interact with skin lipids. Oil “absorption” and skin penetration are two different things. Susan at the Swift Crafty Monkey website researches and writes about topics like this on a regular basis. There’s a minimal charge of $3/mo. to become a member. If you want answers to “why” questions without having to do the research yourself, joining may be a good option for you. Alternatively, follow the tried and true formula and methods from your source and trust that refinement over time perfected the product.

 

[natik]

Thanks, @Mobjack Bay . I am signed up for Crafty Monkey website. That's where I have learned how to make lotions and creams. It is a very informative one.