I’m super excited to present my very first whipped soap recipe—Labdanum & Fir Whipped Soap! The road to this recipe was paved with lots of brainstorming, many experiments, and a fistful of earplugs to prevent hearing loss from very dedicated use of my electric beaters. I’ve devised quite a few different ways to turn my basic cream/whipped soap base into something lovely and wonderful, and this is the first I’ll be going over. It produces a beautifully light, aerated soap that makes a divine shaving cream and just might convince your toddler to take a bath. So, let’s get started!
First off, you’ll need a batch of some 50/50 NaOH/KOH soap paste in a jar. Once that’s softened up (which takes a full 24+ hours, longer than plain liquid soap), the fun begins.
Now, you can whip it up from here, and that’ll work pretty well at first. You’ll be amazed at all the amazing whippy-ness, and how it looks like whipped cream and is just amazing. It’ll multiply in size over and over again, and you’ll be thrilled. But then you’ll wait a day or two, and it’ll seriously deflate into sort of sad, dried out crusty thing. So, if you want to whip it straight away, use it straight away (it won’t be terribly soapy, either, since it’s mostly air—kids will probably love it).
If you don’t want to use it all right away, we’ll need to stabilize the soap. That’s where stearic acid comes in. Stearic acid is a hard fatty acid. It’s very common, and can be derived from animal fat or some vegetable oils, like shea butter and palm oil. I have not had much luck finding pure stearic acid that says it’s been sourced from tallow, but the EWG says stearic acid is “primarily derived from rendered fat of farm and domestic animals”. Anyhow, all that is to say I’m not certain what the source of mine is. If you want to avoid stearic acid, some of my other whipped methods use other things, so stay tuned for those 🙂
Anyhow, I’ve chosen stearic acid here because it has a relatively low melting point (about 70°C), so it will melt in a water bath. It also hardens back up quickly, and lends fantastic structure to the whipped soap, which is otherwise very prone to running off into overly whipped fluff land in an instant.
We’ll melt the stearic acid and softened soap paste together in a water bath. Be extra super sure that the stearic acid has melted completely, otherwise you’ll find wee beads of stearic acid in your final product. If that does happen I suppose you can just call ’em exfoliating beads, but I’d definitely recommend avoiding that in the first place.
Once everything is melted together, we add some vegetable glycerin, and we whip! The glycerin serves to hydrate the soap enough to whip it up, but it doesn’t evaporate off in the same way as water, which would dry out the soap.
When you’ve got a lovely whipped consistency, it’s time for essential oils, clays, and anything else you’d like to add. After that you’ll want to gently spoon it into a jar for storage and use. You can use it straight away, though I’ve found it softens up in the first few weeks, so be prepared for a bit of a texture change.
And we did it! Whipped soap! Exciting 😀
2019 update: I’m afraid I can’t offer much in the way of detailed troubleshooting information for this project as I haven’t made whipped soap in well over 4 years and my memory of the process is limited to my notes, which you’re reading here. Sorry! As you can see, it worked well for me back in 2014, but it has been a long while since I’ve made it.
Labdanum & Fir Whipped Soap
100g | 3.5oz cream/whipped soap base
100g | 3.5oz just-boiled water
Combine the soap paste and the just boiled water in a container with a tight fitting lid. Mash the paste down so it’s submerged, seal the container, and leave it for at least 24 hours for the paste to absorb the water and soften.
Once the paste is all softened up it’ll be quite thick and a bit slimy. Place it in a double boiler with the stearic acid and melt everything together. Make sure it’s really, definitely melted so you don’t end up with little beads of stearic acid in your final product.
Remove the paste from the double boiler and transfer it to an electric beater friendly bowl. Give the paste a quick whip—not much will change. Now add 2 tbsp of the vegetable glycerin and beat it all together. The mixture will start to turn white and look a bit whippy. Beat in another 2 tbsp of glycerin—at this point mine sort of looked like a smoother version of whipped cottage cheese. No worries! Add the last 2 tbsp of glycerin and whip it up—you’ll end up with a beautiful, light whipped soap.
Blend in the essential oils (tweak the amounts to make your nose happy) and the clay. Gently spoon the soap into some pretty containers with lids. You can use it right away, so pop it on your bathroom counter and enjoy!