Soap milling, also called French Milling, is an easy traditional process for enhancing cakes or bars of soaps. Milling allows you to add a variety of healing, soothing, or cleansing ingredients, such as extra fats or oatmeal or essential oils, to your soaps. I like to make hand milled soaps to give as gifts as well as to add luxury to our daily lives.
I’ve used two methods for hand-milling soaps. This method uses heat and works better for soaps you intend to mold. The second method uses warm water, making it a terrific method for kids, and works better for making soap balls and hand-sculpted bars.
Milling Soap Tutorial
This is a basic procedure, not a recipe. I haven’t included specific measurements but have instead described the process and what to look for as you’re working. For specific recipes using this technique, see The Practical Herbalist® Recipes.
Equipment you’ll need to mill soap:
- a mixing bowl
- a cheese grater
- a non-reactive pot
- a rubber scraper or a spoon
- soap molds
- waxed paper (optional)
Ingredients for milling soap:
- One or more bars of unscented, natural soap
- 1/2 cup of warm to hot water for every 4 ounces (approximately 1 cup, grated) soap
- essential oils, herbs, abrasives, or other ingredients
Procedure for milling soap:
- Grate the soap into a mixing bowl.
- Add water, approximately 1/2 cup per 4 ounces of soap, and stir well.
- Heat the mixture on low setting, stirring constantly until the soap is melted and thoroughly combined with the water. It should be about the consistency of a soft cookie dough.
- Remove the mixture from the heat.
- Add any further ingredients, such as herbs, honey, or abrasives. Do not add essential oils yet because the heat will cause them to evaporate.
- Stir the mixture until it’s cool but still pourable.
- Add any essential oils and stir thoroughly. Try adding 4 or 5 drops of essential oil for every cup of soap you grated.
- Spoon into molds, pack the soap well so there are no air bubbles.
- Set the molds aside to dry and harden.
- Once the soap is hard enough, turn it out of the molds and set it on a wire rack or waxed paper to harden thoroughly. This may take a few weeks.
Finishing and Storing your Hand-milled Soap
After your soap has dried and hardened thoroughly, which may take as much as a few weeks, store it in an air-tight container. It will last for a long time, but after a few months any scent you have added to it may lessen. You can re-mill the soap to add more essential oils to it, if you wish.
