Soleseife (Brine) Soap

Soap made with salt has always fascinated me, but I have never tried to make it. Today that will change!

There are two ways to make soap with salt. The first way is to simply add salt to the soap batter for a scrubby bar. This works well using fine sea salt, and the bars have a long life in the shower. I’ve purchased some from friends and enjoyed them very much.

The other way to make salt soap is to make a salt brine. You add salt to the hot lye solution and stir it well to dissolve the salt. You don’t want to go over a 20% salt solution. This is known as Soleseife soap. (“Soleseife” is German for “brine water.”) You’ll often find Soleseife soaps featured in spas for their nourishing and hydrating effects on the skin. Soleseife bars are not scrubby; they are hard, smooth bars.

I opted to go with the brine soap for my first salt soap attempt. I used our usual 6-5-4-1 formula for the oils, choosing Grapeseed Oil as my luxury oil. I’ll scent my soap in Awapuhi Seaberry, a clean and fresh scent that is one of our most popular.

Join me in the workroom to make some Soleseife Soap!

What You’ll Need

Recipe

6 ounces Soybean Oil
5 ounces Coconut Oil
4 ounces Olive Oil
1 ounce Grapeseed Oil
2.21 ounces lye (8% superfat)
2.21 ounces salt
10 ounces water

Instructions

Before you get started, get prepared to soap safely. Long sleeves, gloves, eye protection, and close-toed shoes are a must. If you have never made cold process soap before, we’re glad you’re here! Please check out this blog post, which is the first in a series on beginning soapmaking.

Weigh all the oils into a microwave-safe container; set aside.

Weigh the fragrance oil into a small glass container; set aside.

Weigh the lye into a small glass container.

Weigh the salt.

Weigh the distilled water. I use a stainless steel pitcher for my lye solution.

Slowly add the lye to the liquid, stirring. Do this in a well-ventilated area. As soon as all the lye has dissolved, and while the lye solution is still hot, add the salt to the lye solution. Stir well until salt has dissolved. (The salt did not completely dissolve in my lye solution, so I poured through a sieve to catch the undissolved salt when adding the lye solution to the oils.) Check the temperature of the lye solution; set aside to cool.

Oils prior to melting.

Stirring salt into lye solution.

Pop the oils into the microwave to melt, using 30-second increments. When oils are completely melted, check the temperature, and set the oils aside to cool.

Here is your break to clean up your work space, set out the mold you will use, visit the rest room. Once the oils and the lye mixture are within 10 degrees of each other and have cooled to about 90-100 degrees F, you’re ready to make soap.

When your oils and lye solution have reached the proper temperature, carefully pour the lye solution into the oils through a fine sieve to catch any undissolved salt. Whisk to combine, being careful not to splash.

Whisking soap batter.

Checking for emulsion using the back of a metal spoon.

Add the fragrance oil, whisking to combine. At this point, your soap batter will already have reached a noticeable trace. Keep whisking until the batter is emulsified. You can check for emulsification by dipping a metal spoon into the soap batter and looking at the back of the spoon to see if the oils do not separate.

Once the soap batter has reached emulsion, carefully pour it into cavity molds and set aside to harden. Using cavity molds for any salt soap is recommended because it hardens so quickly, cutting a loaf of soap may be impossible.

Pouring soap into a cavity mold.

Filled all the cavities in one mold. so I used a second one.

Notes

I was amazed that this soap was not super hard the next day when I unmolded it. It was firm enough that it came out of the paw print mold whole, but it was still a bit soft around the edges. It will need to cure for a while before it’s okay to use. I’m sure that is because I used a lot of water in the soap batter.