Liquid Soap Making Tutorial

The first thing I must say before I get started is that I couldn’t have made and truly understood liquid soapmaking with out reading Catherine Failor’s book Making Natural Liquid Soaps. I strongly suggest buying this book and reading it over before attempting liquid soap. The method I use on this page is her paste method which I find very easy to make. The reason I am writing this web page is because I understand that when you are on a soap journey, the more information the better.

From Liquid Soap

The recipe
366 g coconut oil
1424 canola oil
400 g Potassium Hydroxide
1204 g water

This method uses a double boiler system, I use two pots, one
smaller than the other, the handles on the top pot hold it suspended over the bottom of the larger pot. I put water in the bottom one and when the top pot is on it, the water level is over the bottom of the top pot.

From Liquid Soap

When you add the potassium hydroxide it will sound like it is going to explode or boil over, but the water does not bubble up at all and it doesn’t even heat us as much as sodium hydroxide so don’t worry.
One more note, I am one of those risk taking soapers who doesn’t even wear gloves when making soap. (this is not a recommended method of making soap!). When mixing the water & potassium hydroxide together and when mixing the soap there seems to be a very caustic steam that comes from the mixture. When I make liquid soap I always wear long sleeves and gloves otherwise my skin begins to burn.

-pre-heat the water in the bottom of your double boiler
– heat and mix your oils and fats like you normally would for cp, using the
temperatures 160 for the oils and 140 for the Potassium/water mixture, they will get to these temperatures very fast so be ready with your hot water in the bottom of your double boiler when you start.

From Liquid Soap

Try to bring your soap to trace, which even with a stick blender is pretty long. It will go through a few stages before it hardens into your paste. It will also keep trying to separate, but keep mixing it until it is VERY VERY thick like a very thick custard or maybe a meringue.

From Liquid Soap

Tip: Try to keep your soap as close to 160 deg as you can, if you go over 160 your soap will boil up over the top of the pot, much less than 160 and your soap will take forever to trace

This is not trace, just a good imitation. It has to get much thicker than this. If you stopped at this point your soap would separate.

From Liquid Soap

Nope, this isn’t it either, keep going.

I am not sure you can tell by this picture, but at some point your soap may look sort of grainy and like it is separating. Keep going, this is normal.

From Liquid Soap

Now this is a stage you have to look out for. This is what your soap looks like just before it starts to puff up and out of the pot. What happens is that the soap gets too hot (you notice that it is in the double boiler.) and it doubles in size.

From Liquid Soap

If you see this start happening get your pot into your sink and let it cool off. I have a sprayer in my sink and I use it on cold and spray the outside of the pot. I don’t have any pictures of the soap puffing up, because I was just a tad too busy making sure I didn’t get caustic soap all over the counter and the floor. That is exactly what happened when I tried a crockpot to make liquid soap. I guess my crockpot is a bit too hot and there is no way to cool it down quickly as the sides are meant for insulation. Catherine mentions this in her liquid soapmaking book, but she says that it is because of the trapped air in the soap. Through my experience I disagree with her theory. It does look as though it is full of air and that is why it is puffing up, but as long as the pot was too hot, I could not stir it down, while using a sprayer to cool the side of the pot immediately made the soap collapse back to it’s original size. Whatever the theory, be aware this may happen and be prepared.

I didn’t get a picture of the most important part of this process, trace, as when the soap came down from it’s puffy stage it collapsed into a solid mass. This is sort of what it looked like, but this is a bit further on in the process, after it has been heating for a while.

From Liquid Soap

Put the soap into the top of your double boiler and bring the heat up. It
will make a very stiff paste, I don’t bother to try and mix it, it is far too thick.
Check your mixture twice for separation 20 min apart. You have to pry the paste away from the bottom of the pot. If it has separated there will be a clear liquid on the bottom. If you find this you will have to mix it up again, which believe me is not that easy, a very good reason to make sure you get it too full trace.

Keep the water in the double boiler boiling for 3 hours. Make sure that your pot is covered, the idea is to get it as hot as possible. After about 2 hours it will start to turn translucent, if not keep cooking it at a very fast boil until it does. Cook for 1 hour after the translucent stage. I have cooked it for about 4 hours once, and it made a beautiful clear batch of soap. I have never tested my liquid soap with phenolthalein so I don’t know how well that works.

From Liquid Soap
From Liquid Soap
From Liquid Soap

Scrape the paste into a pot of 4820 ml of water for dilution. Break it up a bit to get it into manageable sized chunks.

From Liquid Soap

Slowly heat up your water/soap mixture to a medium heat and then turn it off overnight.

From Liquid Soap

Make sure the pot is covered. If your soap is high in soft oils (which this recipe is) it will get a skin on it if it isn’t covered. Once you add the borax it will fix this but until that time, keep the lid on all of the time.

If you have lots of coconut in your soap it will completely melt overnight. If it is high in soft oils (again which this recipe is) you will have to reheat it in the morning to get rid of the last of the chunks. In the morning heat up your mixture to just warm and melt any leftover chunks, again making sure you keep the lid on until it warms up.

The soap doesn’t have to be very hot. Add your neutralizer, I use borax
56 g borax
112 g water
Heat up the water and borax mixture in the microwave until the borax completely melts. This is harder than it sounds. Borax will not melt until it is very hot and it will become solid again as soon as it cools so you have to heat it up just before you add it to your soap. When the borax is melted it will be as clear as water.

From Liquid Soap

When you add your fragrance to the soap it may cloud the soap., the soap will clear again as it cools.

From Liquid Soap

Sulfated castor:
This recipe should give you a very clear gel like liquid soap, but to get it totally clear you have to make a soap that is at 0% superfat. You are a soapmaker so you know that soap made with no superfatting will leave your skin quite dry. The only thing that will superfat this soap and not make it opaque is Sulfated castor oil. It is kind of hard to get, and really if you don’t care if your soap is transparent, you can use any oil that you like. I like the clear soap so I hunted down the Sulfated castor. [See understanding liquid soapmaking for an update about superfatting]
-add 70g of sulfated if you are using it, and fragrance. If you get the mixture too hot, you may want to wait for the solution to cool down a bit to add the fragrance, otherwise it will vaporize. Let it cool and voila, liquid soap.
It seems complicated at first, but once you do it a few times it becomes much clearer. Remember what CP seemed like when we first started.

From Liquid Soap

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  1. Great post.

  2. great post! Thamks

  3. This looks like a lot of work

  4. Very cool post! I made my first batch of liquid soap by accident this week. So far so good. It should be ready for bottling by tomorrow morning. It has taken several days so far to get it dissolved, but that's because I work two jobs and have to wait so long between soaping sessions. Is the Borax completely necessary? I'm not sure what the current ph is. I superfatted the original batch at around 5%. Thanks for the article.

  5. Fab post, I have a pot of this on the go as I type and it was very reassuring to be able to check the stages with your pictures......fingers crossed it ends up ok!! And thanks for sharing!

  6. My liquid soap is thick and clumpy. It keeps forming a skin on top. I want to make shower gel, and need it to be thick. I am just wondering if I should make this soap thinner, and after it has been sequestered, should I insert additives to thicken it up again?

  7. How long did it dissolve? I have been trying to dissolve mine for 2 days now. I had to cut the batch twice already and it still looks like soap paste.

    I estimate at this rate I will have 4 gallons of liquid soap

  8. This is a great tutorial. Mine came out fine just like above, and was nice and clear at first dilution but when when I diluted it some more about a week later it went cloudy, I used boiled soft water, was this the reason? How can be sure it does not go cloudy, I did not add any essential oils or fragrances at all.

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