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Cold process recipe of a refreshing castile soap, made with 100% olive oil and peppermint and rosemary essential oils and colored with ultramarine blue. The look and scent of this soap reminds the freshness of water or ice.
The scent of rosemary and peppermint essential oils, both as a blend or stand-alone is something that really pleases me. I love the scent of both plants when they are fresh. Peppermint contains menthol, a substance that causes a chemical reaction in your skin, pretty much like a “cold” sensation. This is also responsible for its overpowering minty scent.
Still, I choose this blend not because of its great scent, but because I believe that mint is one of the few scents that “goes well” with the color blue; and I wanted this soap to be blue.
The soap was colored with ultramarine blue mineral colorant, not at its strongest or its weakest. It was the perfect middle color. I hope I can reproduce it more often.
As this is a 100% olive oil soap, it tends to gain soda ash very easily (as I’ve learned the hard way) because it’s a 100% soft oils’ soap. If you want it to get as little soda ash as possible, don’t do like me and remove it from the mold only 6 to 7 days after making the soap. If you actually like the looks of soda ash on soap (I do) remove it after 2 days, as it is the minimum time to harden and with the addition of sodium lactate, it should be ok.
Try this recipe at home and enjoy your soaps!!
More Herbal Soap Recipes:
- Homemade Lavender Soap Recipe
- Homemade Rosemary and Eucalyptus Soap Recipe
- Homemade Rosemary and Lavender Soap Recipe
Watch this video for Soap Making Safety instruction
Watch this video for the Cold Process Soap Making tutorial
- Immersion blender
- Pyrex or stainless steel bowl
- Heat-resistant jug or pitcher for lye solution
- Digital scale
- Digital thermometer
- Measuring spoons
- Rubber spatula(s)
- Small strainer
- Cup / bottle for after trace ingredients
- Soap mold
- 208 g distilled water
- 116 g lye (100% sodium hydroxide) (4,09 oz)
- 2 tsp fine salt / sodium lactate (8 ml)
- 900 g extra virgin olive oil (31,75 oz)
- 2 tsp ultramarine blue – CI 77007 (optional) (8 ml)
- 22,5 ml essential oil blend
Essential Oil Blend
- 15 ml essential oil rosemary (6 1/2 tsp)
- 5 ml essential oil peppermint (2 1/2 tsp)
- 2.5 ml essential oil cedarwood Atlas (1/2 tsp)
|Refined olive oil||Lye||Sodium lactate|
|Grapefruit seed extract||Blue Mica|
|Essential oil rosemary||Essential oil peppermint||Essential oil cedarwood ATLAS|
|Rectangular soap molds||Pretty shaped soap molds||“100% handmade” molds|
|Buy Immersion Blender Set||Buy Pyrex bowl (4lt)||Buy easy pour pitchers|
|Digital scale||Digital thermometer||Measuring spoons|
|Safety gloves||Safety goggles||Safety mask|
- Wear goggles and gloves! Look at “Safety Recommendations” in the video above or in How to Make Soap From Scratch
- Watch the video above about "Cold Process Soap Making tutorial" or read the post How To Make Soap by Cold Process Step-by-Step for instructions on cold process soap making before starting. These are generic but important steps for all recipes.
- Assemble everything: ingredients, equipment, safety equipment. Prepare your workstations. Measure all the ingredients. Don’t start the recipe without having everything ready!
- Measure the colorant and mix it in 1 tsp of olive oil (this oil will be superfat)
Heat the Oils
- Heat the olive oil to approx. 45ºC
Make the Lye Water
- Add the sodium lactate to the water. Make the lye solution according to How To Make Lye Water. Mix it until the vapors start to dissipate.
Make the Soap Batter
- Strain the lye water to catch all clay and lye crystals.
- Use as a target temperature 40ºC – 38ºC for the oil-solution mixture. If necessary, you can reheat the oils, but not the lye solution.
- Add the colorant to the mixture. Use the immersion blender to reach trace.
- Add after trace ingredients: the extract and essential oil (s). Stir with just a spoon (although there is no real danger of a soap batter seizing with olive oil soap).
Molding and Curing
- Pour the soap batter into the rectangular molds with a pitcher and sprinkle with alcohol or witch hazel.
- Let it set from 2 to 7 days. The longer you leave your soap bars in the mold, the smaller chance to get soda ash.
- Unmold and let the bars cure for 4 to 6 weeks. See How To Cure Soap.