I have written before about the many benefits of using salt, both internally and by transdermal application. A fun and easy way to incorporate some of these benefits into your daily routine is by adding salt to your homemade soap. Salt is an inexpensive additive that transforms a regular bar of soap into a luxurious sea salt soap bar that gently exfoliates and softens your skin.
If you are new to soapmaking, I would recommend reading my tutorial on how to make cold-process soap so you have a good grasp of how to make soap before you get started with this variation.
There are a few important things to understand about adding salt to soap that make it a bit different than traditional soapmaking. Let’s get started…
Adapt The Recipe
Your favorite soap recipe will need to be adapted before adding salt. When salt is added to soap it greatly reduces the lathering abilities of the average soap recipe. In order to counteract this effect, you will need to increase the amount of coconut oil to at least 70%.
Coconut oil makes large, fluffy bubbles so this high amount is able to give salt bars a nice lather, but it also can be very drying when used in large amounts. Typically, you would use somewhere between 15-50% with a 5-8% superfat.
Because this recipe will be using 70% coconut oil, I have increased the superfat to 15%. There is a bit of slip when I am rinsing the soap off but I have not found it to be excessive and this soap does not dry out my hands. You could definitely try a lower superfat percentage, just be sure to recalculate your recipe to find the correct amount of lye needed.
What Kind Of Salt to Use for Soap?
A better question is what kind of salt should you NOT use. Dead Sea salt and epsom salt are not advised. Dead Sea salt has a very high mineral content and epsom salt is high in magnesium. Both will draw moisture from the air and make a sweaty, weepy soap.
Sea salt and Pink Himalayan salt are both wonderful choices. The size of the salt grain is a matter of personal preference. I used a large grain but you can certainly use a fine grain if you prefer. The warm water dissolves the salt as you are washing so it is not rough or sharp on your skin.
How Much Sea Salt?
There is really no set rule regarding how much salt should be added. Anywhere between 50-100% of the amount of soaping oils can be used. For everyday hand-washing I like 50% because higher amounts can be slightly drying to your hands, but a higher salt percentage makes a great body bar for the shower.
This number is calculated by the weight of the oils alone, not the weight with the water and lye added in. So for example, if you want 100% of the oils you would use 32 oz of salt for 32 oz of oils.
Adding Salt and Molding
The salt is added after the lye/water has been mixed in and your soap has reached trace. Just pour it in and mix it with a spoon. The soap will set up fast once you add the salt so it is important to move fairly quickly. In fact, you will probably need to spoon the soap into the mold rather than pour it.
If you will be using a traditional log mold your salt bars need to be un-molded and cut about an hour or so after they are poured into the mold. This type of soap gets hard quite fast and if you wait too long you will end up crumbling the soap when you try to cut it.
Personally, I find it the easiest to use individual cavity silicone molds for this project. I leave them overnight and they just pop right out with no problems.
I have a set of supplies I keep on hand for making soap. You can use your kitchen tools if you are diligent about cleaning them thoroughly, but I prefer to keep them separate.
- Glass canning jar or high quality pitcher for mixing lye and water
- Second glass jar or disposable plastic cup for measuring lye
- Non-reactive pot or slow-cooker for warming oils
- Small glass bowl for measuring essential oils (optional)
- Digital infrared thermometer or 2 candy thermometers (one for lye and one for oils)
- Soap mold- (I used these tree molds in the picture)
- Immersion blender
- Digital scale
- Spoon for mixing lye
- Protective gloves and eyewear
- Vinegar for final clean-up
Sea Salt Soap Ingredients
All measurements are by weight. This recipe has a 15% superfat and makes 2 lbs of soap.
- 11 oz coconut oil
- 3 oz olive oil
- 1 oz castor oil
- 1 oz mango butter
- 8 oz Himalayan sea salt (or natural salt of choice)
- 6 oz distilled water
- 2.3 oz lye
- .5 oz lavender essential oil (optional)
Sea Salt Soap Instructions
- Prepare your mold. If you are using a wood mold it will need to be lined with wax paper. Silicone molds are ready without any special preparation.
- Place the glass canning jar on the scale and tare your scale. Pour distilled water into the jar until it reads 6 oz. Set aside.
- Put the second jar on the scale and tare the scale. Wearing your protective gear, carefully pour lye into the jar until your scale reads 2.3 oz.
- Take both jars and your spoon outside. Still wearing your protective gear, slowly pour the lye into the water. Stir the mixture. It will become quite hot so keep this in mind if you need to move it. Let this mixture sit and cool to about 100 degrees.
- While the lye is cooling, measure all other oils EXCEPT the essential oils and warm them together in your pot or slow-cooker. Once they are melted, remove the oils from the heat and let cool until 100 degrees. I use the infrared thermometer about every 5-10 minutes to test the temperature. This works really well. A candy thermometer placed in each container also works. If one is cooling faster than the other you can put your oils back on the heat source or the lye/water mixture in a warm water bath to slow the cooling process a bit. Ideally, you want the lye water and the oils to both be around 100 degrees and within 10 degrees of each other.
- When the temps match, slowly pour the lye/water into the oils. Use the immersion blender to bring the batter to a light trace. It should be slightly thick and resemble cake batter.
- If you are adding essential oils now is the time to do so. Pulse the immersion blender a couple of times to incorporate the essential oils. If you prefer not to use them just skip this step.
- Add salt. Stir until it is evenly distributed.
- Spoon the soap batter into your prepared mold. Remember that the soap is not fully “cooked” yet at this point and could still irritate your skin so you should still be wearing your gear.
- If you are using a silicone mold with individual cavities you are done! Let it sit for 24 hours and then you can un-mold your soap.
- If you are using a log style mold, keep an eye on your soap and as soon as it is set (after approximately an hour) un-mold it and cut it into bars. If you wait too long it will become too hard to cut.
- Stand bars up in a dry area with an inch or so of space in between to allow for air circulation and let them sit for 4-6 weeks. This will allow the soap to complete the saponification process and also dry them out a bit so they last longer in the shower.
Since my skin tends be slightly more oily, I found this soap to be great for my face. If you want an exfoliating option to your normal bar soap, I think you’ll like this recipe!
Do you use salt in your beauty care? Will you try adding it to your soap?