Easy, Beginner DIY Liquid Castile Soap Recipe
Made with only olive oil, this pure liquid Castile soap is easy to make and mild. It’s perfect for face and body, and for cleaning around the house.
A couple of years ago, I showed you how easy it was to make a basic beginner soap, even if you’ve never done it before.
Making solid soaps can be a lot of fun, but not everybody likes using bar soap. Many people prefer using something in a dispenser like a shower gel or a liquid soap.
I made many different types of bar soaps before attempting to make a true liquid soap. There aren’t as many resources about making liquid soaps, so I had to do a lot of trial and error before posting this first liquid Castile soap recipe.
Once you find a good recipe, it’s pretty simple to make. While it does take a little more time and effort than whipping up some bars of cold process soap, I think you’ll find that it’s well worth it, especially when you take a look at the price of a store-bought liquid castile soap.
How does liquid soap differ from bar soap?
The main difference between bar soaps and liquid soaps is the type of lye used to make them. Liquid soaps are made with KOH, or potassium hydroxide, rather than NaOH, or sodium hydroxide.
You can read more about the different types of lye in my post about lye and why it is needed in soap.
While some people like to make a “liquid soap” of sorts by diluting bar soaps in water, you can’t really get a true, transparent liquid soap that way. Some people are happy with the result, but every time I’ve tried it, I’ve ended up with a gloopy mess. It doesn’t have the same cleaning power as either a bar soap or a true liquid soap, and the texture and appearance aren’t the same either.
What is pure Castile soap?
Technically, by definition, Castile soap is a type of soap made with only olive oil. The name “Castile” soap originates here in Spain. (You can read more about the origin of Castile soap and other soaps in my post with a recipe for pure Castile bar soap.)
Over the years, the definition of Castile soap has broadened to include other types of vegetable oils such as coconut oil. Dr. Bronner’s liquid Soap, which may be the most famous commercial liquid Castile soap, actually has a greater percentage of coconut oil than olive oil. (I made a Dr. Bronners liquid Castile soap copycat recipe for those who are interested!)
When it came to making a homemade liquid Castile soap, though, I was a bit of a purist and made the real deal: a soap made with only olive oil.
Olive oil in soap
Soaps made with different oils have different properties.
Soaps made with olive oil are more conditioning for your skin than soaps made with coconut oil. On the other hand, they don’t lather up as much as a coconut oil soap, nor do they leave you feeling squeaky clean in the same way (partly because they are more conditioning).
Some people find pure Castile bar soap to be “slimy” and not cleansing enough. On the other hand, pure coconut oil bar soap can be drying.
- Pure coconut oil soaps are great for general cleaning and for laundry. That’s why I made my homemade laundry soap only with coconut oil.
- Pure olive oil soaps tend to be gentle on the skin and great for gentle body cleansing.
Read my post about the properties of different oils in soaps.
Ideally, you’d combine different oils to get the qualities you want for your soap. That’s exactly what they did when they formulated Dr. Bronner’s soap, and what I did when I showed you how to make a basic beginner soap which uses a combination of olive oil and coconut oil.
Combining liquid soaps
When you make a bar of soap, you have to decide what combination of oils you want to use from the very beginning and your entire batch will have that very same combination.
With liquid soaps, though, you have the advantage of being able to combine your various soaps after the fact, making it easier to experiment with smaller combinations until you find the perfect soap for your need.
That’s why I made a pure liquid castile soap, using only olive oil, and then later made a pure liquid coconut oil soap. Once you’ve made both of them, you can combine them, as needed to get the type of soap you want.
Coconut oil liquid soap vs. liquid Castile soap
When I first started making liquid soap, I assumed that liquid soaps would be just like bar soaps. The difference between a pure Castile bar soap and a coconut oil-based bar soap is HUGE!
I was very surprised to find, though, that liquid soap made with coconut oil was actually quite similar to that made with olive oil. Sure, the olive oil-based liquid soap was darker in color than the coconut oil-based liquid soap. For me, that was probably the most notable difference.
Yes, the coconut oil soap does make a bubblier lather than this one and may be slightly more drying. It does give more of a “squeaky clean” feeling.
In the end, though, the difference isn’t as pronounced as I expected. In fact, I normally just make the coconut oil liquid soap recipe these days. I can buy refined coconut oil cheaper than olive oil, but also love the look of a lighter-colored soap. I also love the fresh, subtle scent of the coconut oil soap when left unscented.
Both soaps give a decent lather. They are also both relatively mild for skin. If you have sensitive skin, though, this soap is probably the better choice.
Those who have very sensitive skin may find that they have issues with the higher pH of any soap. In those cases, it may be best to use something like my DIY Baby Wash and Shampoo. (I made it pH balanced for a baby’s delicate skin.)
Ingredients
This soap uses 4 main ingredients: olive oil, potassium hydroxide, water, and glycerin.
You can use extra virgin olive oil or a lighter olive oil. What is important, though, is that you are using pure olive oil. (If it’s not pure olive oil, it may need a different amount of lye.)
For the water, it’s best to use distilled water. Tap water has minerals and may have other impurities that can affect the clarity of your soap.
Why use glycerin when making liquid soap?
One of the methods of making liquid soaps is called the glycerin method. It replaces part of the water with glycerin.
Adding glycerin moves the soap-making process along more quickly. Because I wanted to share a beginner liquid soap recipe, I chose the glycerin method to have this soap be as quick and fool-proof as possible.
Using glycerin may have some other benefits:
- The resulting soap paste dissolves very easily in water. I don’t need to heat the water nor do I need to leave it for days at a time. I can cover my soap paste with distilled water and usually, in a couple of hours, I have a beautiful, clear liquid soap effortlessly.
- Glycerin is a humectant, meaning it draws moisture into the skin. I find that even my liquid coconut oil soap doesn’t feel drying, despite the fact that it hasn’t been superfatted at all. I think the extra glycerin helps to make a really great, hydrating soap that is clear and doesn’t need extra oils. (I think my homemade glycerin bar soap has the same benefits.)
Materials
To make liquid Castile soap, you only need a few basic tools. An immersion blender helps mix the oils and lye solution quickly so the soap reaches trace faster. A slow cooker works beautifully for keeping the soap at a steady, gentle heat while it cooks. A kitchen scale is also important here, since soap making relies on accuracy. Measuring by weight instead of volume helps ensure that your recipe turns out perfectly every time.
Procedure
Making a liquid Castile soap isn’t difficult and it can save you a lot of money.
To get the clearest soap we can, we’ll use a hot-process method. That means that we will be cooking the soap. During the cooking process, the saponification process will complete and our soap will be ready to use immediately afterwards. (Liquid soap doesn’t need a curing time in the same way as bar soap does.)
The easiest way to make this and have it come out perfectly is to use a slow cooker. If you don’t have access to a slow cooker, though, you can also try baking it in the oven. (I showed how I used this method in the post and video for the coconut oil liquid soap.)
Making the lye solution
Weigh out the glycerine, water, and potassium hydroxide (KOH).
Add the glycerin to the water and then carefully add the KOH to the water and glycerin mixture. (Not the other way around!) Make the lye solution in a well-ventilated area.
Stir the KOH into the water until it dissolves. It will be cloudy at first, but then it will clear up.
Making the soap paste
Measure out the olive oil and heat it over low heat directly in the slow cooker.
Slowly add in the the KOH mixture to the warm olive oil, and gently stir them together over low heat.
Once combined, use an immersion blender to blend the ingredients together in the slow cooker. In a few minutes the mixture will begin to thicken and look like mayonnaise. Soon after, it will look like a creamy pudding. (If you aren’t doing this over heat, it will take a bit longer.)
A few minutes later, the mixture will begin to look grainy and look like mashed potatoes or applesauce. Continue to blend.
If, at any point, the mixture becomes too thick to blend with the immersion blender, switch to mixing with a spatula or wooden spoon. It’s also a good idea to take breaks during the blending process so as not to burn out the blender.
As you continue to blend, it will start to get creamy again. It is now time to cover it and cook it for a while.
Cooking the soap paste
Cooking the soap paste will allow the soap to finish the saponification process and will also help achieve a perfectly clear liquid soap immediately. The process will take 3-4 hours, and you will want to check on it and stir it up every half an hour or so.
As you cook the mixture, it will begin to thicken up and become more translucent.
To check for “doneness,” we will look to see if our paste is dissolving into a completely clear liquid soap. To do this, take a small amount of the soap paste and dissolve it in water, and look to see if the water is clear once the soap paste is dissolved.
If the liquid is cloudy, you should continue to cook the soap in the slow cooker. Let it cook another half an hour before checking on it again. If it dissolves clear like the soap in my picture, you are finished making the soap paste.
Note: If you aren’t using distilled water, the soap paste may stay cloudy no matter how long you cook it! (For more reasons your soap paste may be cloudy, read my post about troubleshooting liquid soap problems.
How to dilute the soap paste
Once you have made your soap paste, you’ll need to dilute it to obtain a liquid Castile soap.
To dilute a soap paste you can:
- Let it dissolve by itself into water over the course of several hours (or overnight).
- Speed up the process by warming the water and soap paste over the stove or other heat source (like the slow cooker).
For clear soap, use distilled water. That will also help ensure the water is free of contaminants and the soap will keep as long as possible. By choosing distilled water, not only are you keeping the possibility of microbial contamination to a minimum, but you are also ensuring that minerals and other substances in your tap water won’t cloud your soap.
If you are making small batches that are going to be used relatively quickly (and aren’t concerned about clearness), you can probably get away with tap water without any issues. I still recommend using distilled water when possible.
Read more about how to dilute a soap paste here.
Customizing your liquid soap
How else can you personalize your soap?
Adding fragrances
Unlike with bar soap, you can add in additives like essential oils after the fact. So, you don’t have to divide your batch at trace and work quickly to make soaps with a variety of fragrances. Instead, you can make a large batch of concentrated liquid soap paste base. The soap paste can be stored away and keeps well for a very long time. (I’ve successfully stored soap pastes for several years without issues.)
You can then add in the essential oils or fragrance oils as you dilute the soap paste. This gives you the freedom, even months after making the soap, to play with fun combinations.
At the time of dilution, I mix the soap paste with distilled water and then I add essential oils to give my soap a personalized fragrance.
Does it need a preservative?
Whether or not liquid soap needs a preservative is a controversial subject. Personally, I don’t use one as the pH of soap is high enough that it’s not a favorable environment for the growth of most of the microbes that we’re trying to avoid.
If I were going to sell a liquid soap, though, I’d do proper microbial testing of the liquid soap to see if a preservative was needed or not. Most natural preservatives on the market aren’t effective at the high pH of soap anyway. (Euxyl® K 900 is an exception and would be a great preservative to consider for using in soap.)
For more liquid soap FAQ’s, read my post How to Make a Liquid Soap: Start Here.
Video
Easy liquid castile soap (made from scratch with olive oil)
Materials
Instructions
- Measure out the olive oil and add it to the slow cooker on low heat.
Make the lye solution
- Weigh out the glycerine, water, and potassium hydroxide (KOH).
- Mix the water and glycerin.
- Carefully add the KOH to the water and glycerin mixture. (Not the other way around!) Do this step in a well ventilated area.
- Stir the KOH into the water until it dissolves. It will be cloudy at first, but then it will clear up.
Make the soap paste
- Slowly add in the the KOH mixture to the warm olive oil, and gently stir them together in the slow cooker.
- Once they are mixed together well, use an immersion blender to blend the ingredients together. In a few minutes the mixture will begin to thicken and look like mayonnaise. It will later look like a creamy pudding.
- The mixture will go through stages, from creamy to grainy and back to smooth.
- As you continue to blend, it will start to get creamy again. Once you reach this point, you can stop blending with the hand held blender and can leave the soap paste cooking covered in the slow cooker.
Cook the soap paste
- As you cook the soap, it will continue to thicken and will become more translucent. To achieve a clear liquid soap we'll need to cook the soap paste for 3-4 hours. During that time, check on it and stir it up every half an hour or so.
Check for doneness
- To check for "doneness," we will look to see if the soap paste dissolves clear. To do this, take a small amount of the soap paste and dissolve it in distilled water. If the resulting soap is clear, the soap is finished cooking. If it's cloudy, continue to cook the soap paste for another half an hour before checking on it again.
Dilute the soap
- To make a liquid Castile soap, dissolve some of the paste in distilled water. I ususally use a ratio of one part soap paste to 2-3 parts distilled water. Let it sit until dissolved, or gently heat to speed it up.
Notes
- A slow cooker is perfect for this because it gently heats without burning and keeps everything at a steady temperature. If you don’t have a slow cooker, you can bake the paste in the oven or cook it in a double boiler.
- Take breaks while blending so you don’t burn out the motor of your immersion blender. If your blender gets too hot, you can pause and let it cook before continuing.
- If the mixture becomes too thick to blend at any point, switch to mixing with a wooden spoon.
- If you’ve cooked it for more than 3–4 hours and it still isn’t clear, there may be other issues. Tap water can cause cloudiness. For other possibilities, see my post on troubleshooting liquid soaps.
- This recipe makes about 4.5–5 pounds of soap paste, which can be diluted to 10–20 pounds of liquid soap or more, depending on how concentrated you want it. That’s roughly 1–2 gallons or more.
- Keep in mind that liquid soap is not as thick as commercial gels or surfactants. It has a thinner consistency and doesn’t need to be thick to be concentrated and work well.
- Undiluted soap paste can be stored in glass or plastic containers in a cool, dry place for more than a year. I’ve had some last for several years without any problems. It may eventually develop a slightly rancid smell, but can still be used for general cleaning.
DIY liquid body soap recipe:
If you would like to combine this soap with a liquid coconut oil soap to obtain a bit more lather and a squeaky clean feeling, try using this ratio:
60-70% liquid Castile soap (made with only olive oil)
30-40% liquid coconut oil soap (for bubbly lather, link goes to the recipe post)
Essential oils of choice.
Mix all of the ingredients together, and keep a bottle in the shower to use instead of shower gel.
Add essential oils for fragrance. Lavender essential oil gives a lovely herbal scent. I also like citrus blends using lemon and bergamot.
What are your favorites?
This post was originally published on June 29, 2016. It was rewritten and republished in June of 2021, adding new information, more photos, and video.
Hello ..
In my soap am getting a settlement of thick forms under the bottle… After shaking it’s getting normal , but every time am getting the settlement understand the bottom … How to solve it …
Hello,
I’m not sure I understand your question. Are you asking about once you’ve diluted the soap, that you get a layer of something on the bottom?
That can be normal, especially in the winter. Allowing the soap to settle should give you a nice clear layer on top. If you need a completely clear soap, I’d actually suggest letting the precipitate settle to the bottom, and pouring the top part into the dispensing jars. If you are getting more than just a small amount it could be due to a number of factors. The cold definitely can affect the clearness of the soap. Also, if you didn’t use distilled water, minerals in the water can affect the final soap.
Hi Tracy,
I tried to make this soap, add all the ingredients as they say in the recipe. But in blending process, after mashed potatoes stage soap did not convert to creamy stage again.
So, I’ve blend it a long time and leave it to cook. After 4 hours is still in cloudy fluffy stage and its not changing at all. I’am putting this aside from heat and hope for your help. 🙂 Do you have idea how I can fix it?
Hi Dragana,
In my experience so far, eventually it all comes around. In any case- even if it never turns somewhat translucent, you should have a usable soap.
Let me tell you about what I did once…
After it had only been cooking for a few minutes, I took out some of the soap paste and set it aside to take pictures comparing the more opaque soap, and the clear cooked paste. I set it aside and forgot to take the pics for several weeks. Know what happened? By the time I wanted to take the pictures to show the difference, the paste that hadn’t been cooked much had already become more translucent and there wasn’t much of a difference between the two.
So, I tried making a new batch, this time not cooking at all. My hopes were that it would eventually turn more translucent too. That was a few months ago, and that paste is still very opaque. Is it usable? Yes! It still behaves as soap when diluted- it just makes a milky looking soap rather than a translucent one.
Those long stories were my way of saying that I’d probably just leave it and try a small amount out.
The paste that you store will likely come around and turn on its own in the next few weeks. Meanwhile, you can still use it. It may not look perfect, but it should be completely usable. If you find it doesn’t behave as soap- then we have a whole other problem, and can talk again to see if we can figure out what happened. 😉
Thank you, I feel relief now. 🙂
Ok, I will leave it stored for few weeks and wait for some change. I hope it will turn out well.
Hi, I got the same result as my soap paste was undiluted. But I cooked for longer then 4 hours. So I decide to diluted anyway and my diluted soap turned out translucent when it has cooled down
Hi Ruthy,
Thanks for sharing your experience!
I’ll have to update the post with the possible situation that could arise. I haven’t had that happen myself, but I think it may have to do with the heat of the different slow cookers or something like that. It’s probably more likely to happen in the winter, too. I do appreciate your help, so thank you!
I thing it was so great to have seen this recipe and it has truly been helpful in going forward
Happy to help!
Hello, i added all of my ingredients as you said into the crock pot and have mixed for 6 min with a hand mixer and it is not thickening at all. How should I proceed?
Hi Cara,
If you have added all of the right ingredients in the right amounts, keep blending. Soaps with only olive oil take a bit longer than others to reach trace. The heat will help speed up the process a little, but it isn’t unusual for olive oil soaps to take longer to go through all of their steps. (When making a pure Castile bar soap using only olive oil, it not only takes longer to get to trace, but it also takes longer to harden enough to unmold- and then should be cured for a lot longer than other soaps.)
Hi Tracy
one more question, for making of bar soap required 6 to 8 weeks for curing what about liquid soap, can i use immediately or need to do curing as well. please help. Thanks.
Hi Rahuveer,
You can use your liquid soap right away. There may be some chemical processes that continue over the next weeks, and the soap may improve with time like bar soap, but in the case of liquid soap, I haven’t noticed much of a difference either way.
During the cooking process, you are finishing the saponification process, so you don’t have to worry about that.
With bar soaps, you want the bars to dry out over the next weeks to have a hard, long lasting bar of soap. Depending upon the method you use for the bar soap, you may also be allowing for the saponification process to complete. Usually that will occur within a couple of days after having made the soap. You could use the soap at that point, but it’s best to wait to allow bar soaps to dry and improve lather, etc.
Thanks so much for the recipe and for the answer. I have had the same question. I’m so happy…
You’re very welcome.
Happy to have helped, Lin! 🙂
HI Tracy,
very useful video, i am planning make shampoo with the same Technic u said, but i want o add pure Aloe vera and coconut milk to improve hair growth, as I need to add water and other ingredients, please advice me on any preservatives. I dont prefer those but i want to know about the self life so that i can prepare that particular amount.
Advice me whether i can use this method for making shampoo and self life of this with out preservative . Thanks in advance.
Hello Rahuveer,
There is a bit of controversy about whether or not you need to add a preservative to liquid soaps because of the introduction of water. While I use preservatives for my other DIY products, I don’t normally use them with liquid soaps, and haven’t noticed any issues. Soap in general has a high pH, in a range that isn’t that hospitable for most bacteria and other unwanted microbes. Because it is in that high pH range, most of the more natural preservatives don’t really work for them anyway. (Preservatives like Leucidal and Rokonsal are usually said to be effective in products with a pH up to 8, but soap is usually higher than that.)
When adding in other ingredients, it’s difficult to know what the outcome will be when it comes to microbial growth. The introduction of something like coconut milk would introduce organic substances to the mix which I’m sure would decrease the shelf life of the product. I personally haven’t done it, so I have no idea what to expect. Without being able to test the final product, it’s really impossible to know about what may or may not be growing in the product.
If I were to do something like that, I’d probably just mix small amounts with the soap before I was going to use it. I wouldn’t try to store it.
In any case, I personally am not a fan of using soap for my hair as a shampoo. I find it really drying. Some people do use it and love it, though.
Thank you very much. It’s really a great help. Thanks for your tips also. I have gone thro lot of info about the shampoo with SLES and ALES both are harmful for the hair so I want to try more organic. Infact I worked in cosmetics R&D. BUT 15 YEARS ago cont remember all preservatives we used. Any way thank you very much I will let u know my experience once I am done.
Great, Rahuveer!
I hope it works well for you.
I personally don’t like using soap in my hair, but I don’t like most commercial shampoos either. I’ve been experimenting with washing my hair sometimes with my homemade conditioner, and have also been experimenting with some more natural surfactants.
I’m not 100% happy with any of my formulations yet, which is why I haven’t put them o the blog yet.
In fact, my plan for January is to take an online course in natural surfactants and formulating natural products using surfactants. My hope is that it will allow me to formulate some great new recipes for my home and for the blog. 😉
Hello. I am Janko from Slovenia. I want to ask you for how long can final soap be stored? Thank you.
Hi Janko,
If you keep most of it in the paste form, and dilute in small batches, it will last quite a long time. I have been saving batches from well over a year ago as a test, and the paste seems to be the same as it was when I first made it. I does depend how you store it, though. I had one container that had a metal lid, where the paste actually contacted that lid, and that affected it badly. In the large jars with metal lids where the paste wasn’t in contact with the metal, I didn’t have any issues.
Hello, Tracy.
I made 100% olive oil liquid soap from this recipe several weeks ago. All looks pretty much like the photos at each stage. I put the paste into jars and, though still clear enough, the paste has gone from chunks to solid in the jars. Does this mean something is not as it should be?
Also, the one larger jar I have diluted really irritates my skin and is also drying my skin. Is there anything I can do to make this more soothing than it is?
I have been using pure olive oil liquid castile soap (Penns Hill) and it really makes my skin soft. I sometimes mix Dr. Bronner’s with this to get more suds and that still works well for me. I use both on my hair with no conditioner and it works fine as my shampoo.
I want to make my own liquid castile to save on the high cost.
Can you tell me what I might have done incorrectly or what I might be able to do to make this more usable and mild on my sensitive skin?
Thank you so much!
Hi Leslie,
Your comment surprises me as I find both this soap and even the one made with only coconut oil to be quite mild. I actually make the one with coconut oil the most often now as I find it the most versatile. I even often use it to wash my face even.
Let’s see if we can figure out the problem…
When you say it started out as chunks and then turned solid…
That sounds strange to me. For me, the paste is sort of like silly putty. It never was really chunky at all, and it definitely shouldn’t solidify.
This may be a stupid question- but let me start with this possibility…
Did you use KOH (potassium hydroxide) or NaOH (sodium hydroxide, aka. regular lye)? You need KOH for liquid soap- and the amount of NaOH would be completely different. If you were to use NaOH, you’d be making a hot process bar soap rather than making a soap paste. The steps would very probably look very similar, but you’d end up with something a bit hard to work with that would eventually solidify.
If that wasn’t the issue, I’ll try to keep brainstorming with you to see if we can figure out the issue.
If that was the problem, I may be able to help you rebatch that soap so that you can at least use it as a more mild bar soap. 😉
Thank you for responding!
I checked the jars again and the soap paste is like silly putty. It’s just that it was more chunky when I put it in the jars a couple months ago and has settled and is not chunky at all.
I did use potassium hydroxide (KOH).
So all looks like it should be ok, but, I just cannot use it because it not only dries my skin (just tried to use the diluted soap a few times to wash my hands), but actually feels like an irritated, almost burning-type of reaction. I tried it a few times, waited a couple weeks or so, then tried it a few more times.
I hope I can figure what is wrong because I’d love to be able to make and use my own soap as I do the ones I purchase…hand washing, showering, shampooing.
Thank you!
Hi Leslie-
Well, that’s good at least-
If you have a liquid soap, even if we can’t fix it for your skin, you can at least use it for general cleaning around the house. I go through a heck of a lot of liquid soap, and have transitioned from a lot of other cleaners. I’ve even been using it successfully in my dishwasher. (I’m not sure that that’s generally recommended, but it’s what I’ve been doing. 😉 )
Do you happen to have any test strips?
Did you dilute it with distilled water?
It would be interesting to see if the pH of your soap turned out excessively on the high side. Soap inherently has a high pH, but if a particular batch has a higher pH than usual, especially if there in unreacted lye, it can be irritating to the skin.
Did you try to neutralize the soap in any way? Or just leave it as is (as I usually do)?
Did you read my posts about my thoughts on liquid soap neutralization?
Sorry for all of the questions- I’m just trying to get as much info as possible so as not to make a bad recommendation.
If I were you, I’d probably mix in some oil into the soap that you want to use for your skin. By doing this, you do risk it getting cloudy. For some people that is a big deal, but personally I’d rather have a cloudy soap than one that irritated my skin.
You can always use an opaque stainless steel or ceramic soap dispenser. 😉 (I actually normally use those, and only use the glass for taking photos of mine for the blog. I wanted people to be able to see what they’d be making.)
The reason liquid soaps aren’t normally superfatted like bar soaps is that people want to make a perfectly clear, transparent soap. If you have very sensitive skin, though, I’d at least try adding a bit more oil to it. By this point, the saponification is complete, so you can now use a more expensive oil that works well with your skin if you like. It should end up being the superfatted component. (Of course you can just use more olive oil too.)
I hope this helps somewhat- I’m happy to try to help you more throughout the process.
I will read about neutralizing the soap. I have not tried that. I will order some test strips, too. And, I can try adding almond or virgin olive oil. Will add comments as I gradually try different things. Thank you for your help!
Oh, yes, I did use distilled water. And, I don’t care much if adding oil makes my soap cloudy, so, that’s fine.
Hi Tracy
Just started making this, didn’t have a blender so I used a hand mixer. Has all gone well so far, and have got to the mashed potato stage and then on to creamy stage – then… it’s now gone to a consistency of shaving foam, instead of translucent streaks. I’m thinking perhaps the mixer added air to it? Shall I just leave it overnight on a low heat and see what it’s like in the morning or keep attempting to stir it? BTW thank you so much for all your information, my 8 year old has inspired me to use less plastic and this is the first step – no more throw away body wash bottles for us!
Hi Lucy,
Yeah, I’d just leave it. I’m sure it’s fine.
Sometimes things look a bit different for some reason or other. I’m sure once you dissolve it in water, you’ll end up with a usable soap. In some cases it may not be transparent, but to me that’s not a big deal. For me the important thing is to have a usable, natural alternative to some of the stuff you’d buy at the store! 🙂
Hi Tracy, thanks for the reply – quick update I left it overnight and then turned the slow cooker on again in the morning and it seems to be doing ok. I’ve had it on for 5 hours now and its still opaque when put into water to test, but i think that’s probably because it is VERY cold in my part of England at the moment!
Hi Tracy,
Thanks for this great recipe. I am about to embark on making my own soaps and lotions. I have looked at other liquid soap recipes but they seem to take too long (2 days!).
I apologise if you have answered these questions but I am keen to get off to a good start:
– can this recipe be adjusted to use a mix of olive and other oils if I didn’t want to make them separately and blend later? If so, what oils would you recommend?
– is this suitable for use on the face, and/or do you have a recipe for a face wash/cleanser?
– do I need to sterilise the storage containers for the paste?
– do you recommend using different equipment for soap making and food preparation (I have seen conflicting advice on this)
Thanks again,
Melanie.
Hi Melanie,
Those are great questions, and I’m happy to try to help you at any point along the way! I usually am very quick to respond, but have only been looking about every other day right now because I’m just getting done with a kitchen remodel and I’m still trying to get the house back together. 😉
1) You can definitely adjust the oils- and I now have a liquid Castile Dr. Bronner’s copycat recipe up on the blog. I’ve actually also been experimenting with making the soap without the hot process part- and will eventually get my findings up on the blog. (Meaning that I think that not only do you not need days to make a liquid soap, but you probably don’t need hours either!)
2) I actually find this suitable for the face and often use it on mine. It is said that bar soaps are gentler on the face because you can superfat them, but I find this soap to be super gentle. Even the coconut one is mild. Perhaps it has to do with the addition of the glycerin. I’m not really sure why, but I find it very gentle. I do have an activated charcoal bar soap that I normally have been using to wash my face, but in the shower I use the liquid soap. (So, on most days I guess I really end up washing my face with my mixed oil liquid soap.) Ha!
I’ve just now started experimenting with surfactants, and will be working on a gentle non-soap face wash eventually. I want to make sure I fully understand and have experimented with them before just throwing recipes up on the blog, though. I have fairly oily skin, so I can handle soap well, but I suspect that people with dry, sensitive skin may do better with the bar soap or with a surfactant based wash.
3) While I don’t sterilize the storage containers per se, I do run my jars through the dishwasher. It’s a good idea to at least run very hot water through them and make sure they are thoroughly clean. I also usually dilute with distilled water. It’s inexpensive, and I figure it will ensure my mixture will last longer. (That said, I’ve never had issues the few times I’ve diluted with tap water.)
4) I personally see no reason to invest in different equipment for soap and food making. Keep in mind that lye is used to cure olives, make the crust on pretzels and sometimes bagels, etc.
I think people think of lye as some super toxic chemical that is going to kill you if some microscopic drop remains in your mixer or whatnot. They then go and eat lye cured olives with no issues.
Lye is a powerful base, and just like a strong acid will burn you if you are’t careful, and it’s fumes can also hurt you. Once you mix with oils, though, you have soap. Even if some lye remains, I just don’t see how it can hurt you. You can rinse everything with vinegar to try to neutralize any remaining bits, but personally I find even that to be an overkill. 😉
Thanks so much for your reply Tracy. I’m on my way to buy the ingredients for this and your basic bar soap recipe. I am really excited about making my own soaps and skincare. I am overcoming my nervousness about working with lye and dealing with pH issues, but I am still a little anxious about preservatives. I don’t want to sell the things I make but would like to give them as gifts. Is there a simple principle about working with preservatives that you could share?
Thanks again,
Melanie.
Hi Melanie,
Well, with soaps you don’t really have to worry about preservatives. Some people say they use preservatives with liquid soaps, but I don’t think any of the natural preservatives work at the pH of liquid soap, and I’ve never had any issues with soaps, even those that have sat around for months and months at a time.
I think that the high pH of soap helps preserve it naturally. It’s a bit of a controversial subject, but I wouldn’t worry about it for home use or gifting. Selling, of course, is a whole other game.
As for other products like homemade lotions, it’s the addition of water to a product that allows for bacterial growth and makes a preservative necessary. I talk more about some of the preservatives I use in the lotion recipe I just linked to with the general guidelines for how long they should preserve the lotion. (The preservatives I use generally say they keep for 3 months, but I’ve talked to people who sell products in the US who use the same preservatives and say they generally have a shelf life on 12-18 months! I’m guessing Europe errs on the side of caution, and have to admit that even lotions I’ve had sitting around for months past the 3 months haven’t shown any signs of anything going awry!)
There are preservatives that allow for longer lasting products, but they are less natural, and most people who follow my blog aren’t interested in using that sort of thing because they are making their own products in the interest of avoiding just that. 😉
Hello Tracy, I am very thankful to have discovered your detailed and easy to understand blog. I have a small cp soap business in rural New Zealand and have recently made your liquid Castille soap successfully. I love it and am not planning on adding coconut because it is so gentle. I’ve noticed that brambleberry sells Castille soap paste and markets it toward the “middleman” , the soap maker, just like a melt and pour soap base. I have this idea and I was hoping you would tell me what you think. I’ve put the soap paste in attractive 8oz jelly jars. I was thinking I can sell the soap in a 200ml pump ready to go but also offer the jar of soap paste for the customer to dilute as needed for approximately 4 refills. I’m finding a 1 part (50g) of paste to 200mls of water to be a good thickness. I think New Zealanders are keen to “participate in the process” and are also looking for the simplest, most gentle products. And also, would diluting it as needed increase its shelf life particularly if an essential oil was added at dilution? Can you think of reasons this might not be a good idea? I would of course give instructions for diluting and would highly recommend the method of patiently leaving it in a jar a day or two. I was also considering whether I should include an option of a 5ml or 10ml essential oil, perhaps lavender that people could add when they dilute their paste. But I wasn’t sure if either size would be enough to scent 4x 200mls of soap… I use essential oils in my cp soaps but I’ve never rebottled them before and don’t know if it’s going to be economically viable yet, just wondering if you had any thoughts on this. I added about 4 g I think( I didn’t have a dropper and my scale was acting up so not very scientific!) to a 200ml bottle of soap and the scent is very faint. I think even if unscented was the only option , people will still buy it because I’ve had success selling unscented Castille bar soap in the past. Thank you for your excellent blog, Tressa
Hi Tressa,
I absolutely LOVE that idea!
I can’t think of any reason that it isn’t a good idea. It’s actually quite genious, and I’d totally buy it if I didn’t make the soap myself. 😉
(If it were bottled up cute enough, I might consider buying it anyway.) Ha!
I also quite like the idea of selling it with a small bottle of essential oil, and do think either the 5ml or 10ml would be enough. That, of course, really depends on the scent and how strong each person likes their scent to be. I personally never measure out fragrance, either, and prefer to go by what my nose says, but small bottles tend to last me awhile, and I use them for lots of different homemade products.
Scents like lavender are popular and do very well in lasting long in soaps as compared to some of the other scents. I love citrus oils, but you need to add a lot more of them, and they don’t tend to last as long. That’s why I usually use them in combination with another scent like lavender or rosemary.
Have you tried making the coconut oil liquid soap? I really think you should give it a try. In the end, it’s the soap I make the most. I feel like I should update all of my liquid soaps to say how the coconut oil soap is my favorite. I actually find it very mild for your skin. Maybe it’s because I use the glycerin method. I’m not really sure, but the final soap is very nice. I rarely make the one with olive oil anymore because the coconut oil one is a lot cheaper to make, and is such a great multipurpose soap that I really love it. I now understand why Dr. Bronner’s soap is mainly comprised of coconut oil. I did do a copycat recipe too, but I think I added too many of the other oils to it which not only increases the price, but it appears to cloud up the soap. (I want to make a new version recipe with my thoughts on the subject.)
Seeing as you’re a professional DIY-er, I’d love it if you’d consider joining my Facebook group. I haven’t been very active in there lately, except to answer questions, but I’d really love to get together a great group of people who make their own products to brainstorm up some great ideas together. 🙂
Hello again, Tracy, Thank you so much for your reply…I really appreciate the advice and will try the coconut liquid soap paste this week. I actually got the olive oil paste and soap all labeled and ready for the cafe shelves where I sell my product and then realised I’d misspelled Castile, as I did in my first comment to you! At the same time, I was having. a slight hesitation about the lack of lather and still weighing up the essential oil option. So all of your comments are very timely and helpful. I live quite “unplugged” as noted by my just seeing your reply today so sorry for the delay. This is the first time I’ve ever written on a blog! As such, I don’t think I would be very active on a facebook group, at least at this time. But I will be sure to check up on your blog from time to time. I really do appreciate your help. Warmest Regards, Tressa
Hi Tressa,
No problem! I completely understand! I just figured that if you were already on Facebook and were going to be experimenting, you might want the opportunity to network with others who are doing the same. A few girls in the group are making the laurel berry soap right now. It’s fun watching how their experiments go.
I’m always here to answer questions, so no worries. 😉
Hi again,Tracy, and thank you. Well I made the coconut soap today and it’s very nice. Then I started to wonder if you’ve ever tried to make a liquid soap PASTE that has the blend of olive and coconut, similar to what you’ve recommended 70% olive and 30% coconut? Or maybe 60/40. I noted the water and KOH amounts are different for your two liquid soap recipes. So I inputed the oils into soapcalc.net but I read somewhere( Your blog?) that there might be a better calculator on line for liquid soaps. Since the glycerin is replacing part of the water, that doesn’t effect the amount of KOH, right? I didn’t see anywhere on the calculator to include glycerin so assume it’s like using milk instead of water?
I’m trying to figure out marketing details by presenting the product line as simply as possible. I’ve done three batches of the olive and one of the coconut, and I was considering selling both a 100% olive and a 70/30 blend already diluted in the pump dispenser. I can then sell the 100% olive oil paste, but thought if I sell 100% coconut oil paste so the customer could blend their own, you’d end up with lots of extra coconut. I’m using pomace olive oil so the price difference isn’t that much, although the olive is $1.50 more per litre. Thanks so much, Tressa
Oh yes, I’ve decided to provide the essential oil blends as you’ve recommended.
Hi Tressa,
I think your soap line sounds wonderful! 🙂
I use the Summer Bee Meadow advanced calculator for my liquid soap recipes. It allows for inputing glycerin.
I have published a post with mixed oils- my Dr. Bronner’s copycat recipe, but the more I use it, the less impressed I am with it- and I actually want to update that post with my thought, findings, and a new recipe that only uses coconut and olive oil. (That recipe adds other more expensive oils like hemp and jojoba, and I don’t really see much benefit from it. Plus, it seems to leave a cloudy film floating on top. I had another reader comment the same to me.) I0m planning on making a new batch in the next couple of weeks and adding my comparison to the post.
My favorite is still the coconut oil liquid soap. I use it the most- and use it for almost everything around the house lately. (I thought I’d like the pure Castile soap (with only olive oil) best, but in the end, I don’t. Here olive oil tends to be a lot cheaper than coconut oil- unless you can find a cheap source of coconut oil for DIY uses online. (It wasn’t until this year that I did finally find a cheaper source- and had to buy a huge tub of it.)
Hi Tracy
Thanks a million for your detailed information
I have a question about liquid soap, please.
I watched a video online on how to make liquid Castile soap thicken by adding salt solution.
When I do this to a certain extent, like 12 tbsp per liter, I get a thick liquid like sauce, but it doesn’t thicken further. It doesn’t become a paste like the video. If I add more, it separates into a clear liquid and foam on top. Why does this happen?
Another question, do I have to leave the Castile soap for 2 – 3 weeks to cure before I use it? Would it behave better if I do? Or shall I use it from the second day?
Thanks a lot.
Hello Mona,
I’m not really sure about the salt solution. I know that salt is often used to purify soaps. Because soap doesn’t really dissolve in salt water, you end up separating the water from the soap and ideally any impurities in the soap will dissolve out in the water. I imagine that after a certain point, you are basically separating the soap from the liquid component.
I personally don’t use salt to thicken my soap as I don’t mind it on the thinner side.
As for the curing…
It isn’t really necessary to wait. Some people think that the soap will improve with time, but I haven’t personally found much of a difference. The curing time seems to be more important with bar soaps where you want the soap to harden so that it will last longer. They do say that there are some chemical processes that continue after having made the soap, which could mean the soap does improve a bit, but, like I say, in practice I haven’t noticed much of a difference. 😉
Thank you very much Tracey. I really appreciate your detailed explanation 🙂 (Y)