When I make liquid soaps I make mine from scratch. Below is a short intro to making your own liquid soap from scratch.
A word of caution, this process is a long process to make and should be attempted by an experienced soapmaker. You do not have to be a professional soapmaker to make your own liquid soap, but I will state that having some experience at making soap is HIGHLY RECOMMENDED. I say this because you will know what 'trace' looks like and how soap is going to react when you add the lye solution to the oils.
Making your own liquid soaps can be a very fun experience and should be a continuing experiment. I am always learning with each and every batch of liquid soaps. You will notice that even if you use the exact same formula each time not all will trace the same way, cook the same way or end up the same way, this allows you to experiment and create wonderful soaps in your own way each time you make a liquid soap.
First off, one of first things you will find when you start to make your own liquid soaps is that certain oils will give you different results to the finished liquid soap you make. For instance, adding palm oil to your formula will cloud your soap, BUT, if you add a small amount of palm oil to your liquid soap with the addition of castor oil, will counter act the slightly clouding of the palm oil in your formula. Castor oil adds extra emoliance to the finished soap, giving your soap a thicker creamier lather. Palm oil, even though it slightly clouds your soap also adds extra oompf to you finished soap, both boosting lather and aiding thickness to your finished liquid soap.
Now, if you are looking for a crystal clear liquid soap, you need a long cook time on it, generally when you are making a liquid soap base (I call this the paste) I cook my 'paste' for a minimum of 3 hours. This is to ensure that all the oils have completely bonded with the lye and are completely neutral. This process is necessary for a completely clear liquid soap. This means there is NO super fatting of liquid soaps, a super fatted soap will be cloudy. If your looking to have a moisturizing liquid soap, then you may want to supper fat your liquid soap a little bit and not worry about the clouding in your formula.
All liquid soap bases are lye heavy, because of this you will need a buffer to help bring the PH down. In liquid soapmaking I use either borax or Cirtic Acid solutions to help bring my soap's PH down. The addition of Borax has double purpose, Borax is both a buffer for your soap and also a thickener, this is my choice when I make my liquid soaps.
Here we GO!
Here is my makeshift double boiler to cook my 'paste' in when I am making my liquid soap base. The larger pot has enough water in it so my inner pot is not sitting directly on the bottom of the pot, the water inside is at a full boil.
Here I have added the lye solution 'potassium hydroxide and water' to the oils:
35oz coconut oil
11oz castor oil
3oz palm oil
'Lye Solution' (also known as potash or soda ash)
13oz potassium hydroxide
39oz distilled water
For liquid soaps instead of using Sodium hydroxide we use potassium hydroxide, because we want a base that is easily diluted into water, has a longer molecular chain, and creates a transparant base when it's finished. potassim hydroxide bases will be soft, like a thick paste that easily dilutes into water. Sodium Hydroxide creates a solid soap while Potassium Hydroxide creates a softer gel paste.
When adding the oils and lye solution together, your oils temperatures should be at or around 160F deg. When you mix the potassium Hydroxide with your water you won't really want to allow the solution to cool, as potassium Hydroxide does not raise your water to 200F deg, instead it only get's to about 160-180F deg. You will want to keep your oils and lye solution at these temps to create and cook your liquid soap paste.
When I make my liquid soap paste, I stick blend for a few minutes, then I use the spatula to continue to stir my oils and lye solution. I do this because if you continue to use the stick blender too long you will risk trapping air into your paste, which slows down the saponification process of your paste, and once you get bubbles in your paste a few things will happen.
1) The air bubbles will not come out of the paste and will take longer for your paste to completely saponify and cook until it is neutral.
2) trapped air bubbles in your soap paste will make your paste to puff up and you run the risk of a 'volcano' effect with your paste. When this happens, you loose a lot of soap paste, you create a HUGE mess, and you also risk being burned by the very hot soap.
So, I use the spatula to help keep the extra air bubbles out of the soap, I alternate, stick blend for a minute or two then stir with the spatula. Once you've made liquid soap for a few times this becomes easier to know when your oils and lye solution is mixed, and when to expect it to start tracing.
Above it's just mixed, it is a milky color but it is still very thin almost like water, it's not seperting so I am stiring it with the spatula to keep those air bubbles out of it.
Here is what it looks like when it's starting to trace, no from the previous picture till this one it took less than one minute to get to this point, it's starting to thicken up.
This is what it looks like 30 seconds later, it's like a thick batch of mashed potatoes. When your making liquid soaps once the base starts to trace it goes very fast, within seconds you will go from a water like mix to a thick potato like paste.
Now the clock starts and the 3-4 hour cook time starts! Put the top on your soap pot to keep it hot, and if you are able to, put the top on your outer pot to help keep all that heat around the inner pot.
Here you are seeing what your soap paste looks like at the half way point, the above paste has been cooking at 1 1/2 hours. As you can see your starting to see it's getting clear. Continue to cook your paste, being sure to stir it every 20 minutes to maintain full saponification and neutrality.
Here we are at 3 hours! The soap base is clear, I tested it and it's completely clear. You can test your paste by heating up a small amount of distilled water take a teaspoonful of your paste, let it melt into the distilled water and if it's clear your soap is done cooking.
Here is another picture of the soap paste at the end of the 3 hour cook time! It's real thick, and tested neutral.
I always let me soap sit over night to let it 'loosen' up a little bit, it will continue to cook while it's in the hot pot over night, just make sure you keep the pot closed to keep the heat inside.
Tomorrow, the soap will have a slightly differnt look to it, being more clear and more 'gel' like.
Tomorrow I will go over the diluting of the liquid soap!