Why do some sites and books say you MUST use lye?

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Camianmears

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I don't have lye in a lot of the soaps I have purchased. In fact one only has five ingredients: Shea butter, palm kernel oil, olive oil, vanilla oil and purified water and it's amazing. Why do these people say you have to use it?

Also I am new to this site and just started making soaps myself :D
 
I think maybe people have a misconception about using lye in soap. You HAVE to use lye in order to MAKE soap. Those oils have been saponified by adding lye to them. But once they are combined with lye, it becomes soap. The properties of the lye changed when it was combined with the oils. So your soap seller is indeed incorrect in saying she didn't use lye. She had to.
 
Thanks for the responses.

The soap i mentioned is from "Out of Africa". I had a feeling they may not have put all the ingredients on the box but that's a bit odd isn't it? Also if i purchase the melt and pour base which has sodium hydroxide already in it, then that means I'm all set with lye right? I can't get lye and add it myself where I live.
 
Also,

I am using melt and pour bases and some do not have sodium hydroxide...so are they not really soap?
 
What about this base? Still not really soap?

I'm just trying to make sure before i invest a buncha money and find out i didn't make soap all along so than you all for all your help!
 
Melt & pour is called soap by the general polulation, just like soda is called 'coke' even if it's pepsi or another brand or how a vacuum is called a 'hoover' even though it may be a different brand.

The FDA offers defintions of what makes an item soap vs a cosmetic, vs a drug. It is based on both content & claims you make.

If you make soap w/ lye & oil & claim it's plain'o soap, it is soap.
If you make soap w/ lye & oil & claim it's mositurising, it is a cosmetic.
If you make soap w/ lye & oil & claim it is anti-acne it is a drug.

If you make soap w/ lye & oil & detergents & claim it's plain'o soap, it is a cosmetic (due to the detergents).
If you make soap w/ lye & oil & detergents & claim it's mositurising, it is a cosmetic (due to the detergents & the claim).
If you make soap w/ lye & oil & detergents & it's anti-acne, it is a drug (due to the claim).

Dove 'soap' is not soap according to the FDA, it is a cosmetic because it has detergents in it.

Soap vs cosmetics vs drugs have different FDA requirements in relationship to labels, etc.
 
This is a particular point of interest for me. I understand the chemistry behind it however specifically what I am interested in is this

Adding lye results in glycerin so for those of us like myself who does not want to handle lye can I use glycerin whether in a soap form or liquid veg glycerin and successfully create a hard or liquid soap?
 
hlawrence said:
This is a particular point of interest for me. I understand the chemistry behind it however specifically what I am interested in is this

Adding lye results in glycerin so for those of us like myself who does not want to handle lye can I use glycerin whether in a soap form or liquid veg glycerin and successfully create a hard or liquid soap?

I'm not sure I understand your question. To what exatly are you adding lye? And by lye, do you mean KOH or NaOH.

Also, when you say you 'understand the chemistry' what are you referring to?
 
hlawrence said:
Adding lye results in glycerin so for those of us like myself who does not want to handle lye can I use glycerin whether in a soap form or liquid veg glycerin and successfully create a hard or liquid soap?

If I understand your question, the answer is no. You cannot use glycerin to replace lye.

If you want to "make" soap from scratch you can only do so by using lye and oils. The simple process of soapmaking is like any other chemical reaction, it requires the basic ingredients and a source of energy. But you can't make water (Hydrogen and oxygen) by substituting another ingredient. Just like you can't make cake by substituting bread crumbs for flour just because they are similar.

You can use a melt and pour base and not use lye. You are not "making soap" in the sense of creating the chemical reaction that is soap making. But you can still be creative and very artistic with M&P soap. Just take a look at the photos section.
 
do a search on the chemistry of soap for a more detailed explanation, but essentially, soap is the result of reacting fatty acids (oils) with caustic (lye). it does result in some glycerin, but also in sodium (if using NaOH) or potassium (if using KOH) salts of the fatty acids - also known as SOAP.

true soap is made using a caustic (lye). some soapmakers choose not to show this on their labels. our soaps are a mix of water, salts of fatty acids, excess oils, and glycerin, plus whatever else we put in there.

commercial soapmakers (like P&G) make soaps very differently. if they are making real soap (the salts of fatty acids), they typically purchase (or make elsewhere) these salts of fatty acids and they purify them - so they don't have the mix of ingredients unless they choose to put them in there. and they don't typically list the caustic. many times they are not selling "soap" per se, but actually detergent products which - chemically speaking - are another animal altogether. they act the same way soap does - as emulsifiers - but are different. detergents are not soaps and are not produced by mixing lye with oils.

oh, and many commercial soaps are a blend of soap & detergent.

yes - adding lye results in glycerin, AND SOAP. glycerin is not the same as soap.

if you don't want to handle lye, you can purchase pre-made soap or a detergent base. it's called melt & pour and is fun to work with.
 
If you want to make soap you have these basic choices:

Cold process (CP) soap making which involves handling lye directly, mixing it with water and fats, and getting soap on the other end. If you make it properly, the lye will be converted into soap (a form of salt) and there will be no lye left in your finished product.

Hot process (HP) involves the same ingredients as CP and also requires handling lye directly but you heat the soap mixture in a crockpot, in the oven, or on a stove top, which speeds up the chemical reaction of turning lye, fats, and water into soap.

Melt and pour (M&P) soap base is sometimes detergent based and sometimes CP based; if CP-based it involved lye in its production. You're not really "making" soap, you're melting it down, adding color and fragrance and letting it harden again. Beautiful soap can be achieved using this method.

Handmilling or rebatching soap. This involves grating up existing soap (CP or a commercial detergent bar like Dove), heating it, and then mixing it with the color, fragrance, or additives of your choice. You wouldn't handle lye directly with this method because it was already used in the manufacture of the soap you grated up.

Hope this helps.

Edited to take carebear's comment into account. She's right; that's what happens when I type too fast.
 
Judy, detergents are not produced with lye. There are MP soaps that are based on true soap, and of course those do involve caustic - but not the detergent based ones.
 
by the way, it can seem that African Black Soap is made without lye - but the (burnt) plantain skins (ashes) are the source of the caustic.
 
carebear said:
Judy, detergents are not produced with lye. There are MP soaps that are based on true soap, and of course those do involve caustic - but not the detergent based ones.

Right you are. I was typing a mile a minute and didn't spell that out fully. I fixed the post. Thanks.
 
That's awesome :) Thank you all so much for your input. I understand from a chemistry angle the reactions that create the soap. It's an evil thing asking someone at a Whole Foods cause that is exactly what they say, "Oh yes I make soap and no I don't use lye." Which is how I came to question glycerin usage. So then my next question is to what degree can you control the contents of your melt and pour. I don't mind doing that but I do prefer 100% olive oil castile soaps and that is what I was going for.

Oh and one more thing! I see ppl talk about Lye being hazardous to use health wise. Is KoH different in that respect at all? I do like the idea of making things by myself primarily because I want to know that what is in there really is there but I really am not so invested in that idea to the extent of risking health problems.
 
The lye is not toxic, but it is caustic, which means it can burn or corrode living tissue. (So just don't drink it)

You need to take precautions to not burn yourself (wear gloves, goggles) but I wouldn't say it was hazardous to your health.
 
hlawrence said:
So then my next question is to what degree can you control the contents of your melt and pour. I don't mind doing that but I do prefer 100% olive oil castile soaps and that is what I was going for.

Oh and one more thing! I see ppl talk about Lye being hazardous to use health wise. Is KoH different in that respect at all? I do like the idea of making things by myself primarily because I want to know that what is in there really is there but I really am not so invested in that idea to the extent of risking health problems.

For the first part - you can control what base you buy and from whom. Read the ingredients carefully. There are many options out there.

As for KOH vs NaOH - same difference when it comes to safety & precautions. Health problems? Don't breathe the fumes (turn your head), and don't splash it on your face or skin or bob forbid your eyes (wear gloves and eye protection and wash quickly if it happens) and you are good to go. It's not uber dangerous - just use it carefully as you would, say, boiling water.
 
carebear said:
by the way, it can seem that African Black Soap is made without lye - but the (burnt) plantain skins (ashes) are the source of the caustic.

You make a form of lye by running water through wood ashes, so my guess would be the burnt plantain skin ashes are also making lye.
 
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