Soleseife or Brine and Salt Water Soap Recipe

A European Soap Variation

Soleseife or Brine/Salt Water Soap

CC0 / Pixabay / Creative Commons

Soleseife or brine soap is becoming a popular product in the bath department, but many shoppers are confused as to what it is. This German soap has all the benefits of a dip in the ocean. It's a great exfoliant. What many buyers don't realize is that Brine soap and salt bars are two different products!

Difference Between Brine Soap and Salt Bars

In a soap and salt bars is that the salt is dissolved, not crystalline. Also, the soap is extra hard, very white, and ​works well in intricate single cavity soap molds.

Most of the German recipes we found added about 25% salt by weight to the water for their soap recipe. So, if you had 10 ounces of water, you would add 2.5 ounces of salt. The lye to water ratio was about 2.5 – that’s multiplying the lye amount by 2.5 to calculate the amount of water needed for the recipe. Because we were trying a new additive, we wanted to use a reliable basic recipe that we were familiar with. We adapted a tried-and-true recipe into a “soleseife” recipe as follows:

  • 10.25 ounces of lard – 25%
  • 12.3 ounces of coconut oil – 30%
  • 12.3 ounces of olive oil – 30%
  • 4.1 ounces of safflower oil – 10%
  • 2.05 ounces of castor oil – 5%
  • 5.8 ounces of lye – a 5% discount
  • 14.5 ounces of water
  • 3.6 ounces of plain sea salt
  • 1.8 ounces of a fragrance or essential oil blend – (I used a blend of 25% cedarwood, 20% rose geranium, 25% spearmint and 30% clary sage)

Prepare the Salt and Lye Water Solution

  1. Weigh out the water and add the salt. Stir well until it’s completely dissolved. Let it sit a bit to make sure that all the salt is staying dissolved.
  2. Add the lye to the saltwater solution. It will turn a milky white color as you stir. As before, let it sit for several minutes and stir again. You want to make sure that all of the lye is completely dissolved. Several of the German sources we found even recommended filtering the lye water to make sure there were no un-dissolved particles.
  3. Set aside the lye to cool.

Prepare the Oils and Make the Soap

  1. Weigh out and melt/mix all of your oils as per the recipe you’ve created.
  2. Mix the lye solution and the oils as you would with any standard soap recipe. When the soap has reached a light trace, add the fragrance or essential oil, and mix a bit more.
  3. Pour the soap into whatever mold you prefer. Because these saltwater bars get so hard, individual molds seem to work best. If you do use a loaf or slab style mold, be sure to unmold it while the soap is still pliable enough to cut.
  4. Let the soap saponify for 12 to 24 hours. It will indeed get hard quickly. We used our 12-bar silicone mold from Bramble Berry, and the soaps popped right out after about 12 hours.
  5. Let the soap sit for a couple of days before testing it, and let it cure for a couple of weeks before putting it into general circulation.

When it was unmolded, the bars were hard, but not crumbly like a traditional crystalline salt bar. The lather was low and milky. It will most likely improve with cure time.