I made my first batch of soap about 15 years ago. It was a big deal since I decided to render beef tallow myself, just for the experience. It added a lot of work and time to the soap making process, but for me was worth the experience. The soap turned out nice—but not terribly exciting. Next I tried a recipe that used olive oil. The soap turned out nice, but again, not terribly exciting. Then, after years of thinking my soap making days were over, I found a recipe that had a combination of rich, emollient nut and vegetable fats, plus coconut milk. This is a very creamy, fine-bubbled moisturizing soap and also doubles as a shaving bar. I'll share the recipe below, but first a little history, science and basics about soap making.
An excavation of ancient Babylon turned up evidence of intentional soap making around 5,000 years ago. It was made from fats boiled with ashes and the resulting soap was used for cleaning fibers used in textile manufacturing. More history of soap can be found on the Today I Found Out web site.
Trivia: Ever wonder how soap operas got the name? It's tied to the excessive amounts of money Proctor & Gamble, Colgate-Palmolive and Lever Brothers spent advertising their soaps on such TV programs. They had the perfect audience!
You must be very specific when measuring soap making ingredients: saponification is a chemical process that requires the correct balance of fats and alkali. Fats (vegetable/nut oils and animal fats) are triglycerides. When triglycerides come in contact with a strong base (e.g. lye), the molecules are split and fatty acid salts and glycerol are released, making what was once oily fat into a water-soluble hygroscope (attracts and holds water molecules from the surrounding environment).
Melted oils and fats are combined with an alkali (sodium hydroxide, commonly known as lye, mixed in water or other liquids). The lye has a chemical reaction with the fats, called saponification. The resulting mixture is placed in a container for 24-48 hours to harden (incubation), then removed and cut into bars and set out to air-cure. The lye eventually deactivates during this time and the fats/oils are turned into soap. The curing process takes about 4-6 weeks to complete.
Tools You’ll Need to Make Soap
- Digital scale
- Non-reactive pot, spoon and spatula
- Bowls of various sizes (for ingredient measuring and lye mixing)
- Plastic or cardboard shoebox, wax paper & tape
- Sandwich baggie
- Hand-mixer or submersible blender
- Thermometer (digital is best; 2 are even better)
- Towels for incubation
- Some sort of drying rack
Warnings: ALL Are Very Important!
- Soap recipes are generally given in weights, not volumes (as stated above, this is chemistry so proportions have to be specific). A scale is necessary.
- Use only non-reactive containers, pots and utensils when making soap. Glass, stainless steel and plastic are all fine.
- Lye can be scary. If the crystals become damp, they will burn through anything. Safety glasses and dishwashing gloves are recommended. ALWAYS pour the lye into the water, not the other way around, to avoid damp lye particles from being disbursed. It's best to mix the lye and liquids outdoors if possible‑there's a gas given off by active lye that you don't want to inhale. Finally, the lye will heat the water to about 200 degrees F.
- Both the melted fats/oils and the lye/water need to be as close to 100 degrees as possible to get them to emulsify properly when mixed together. Any additional ingredients (fragrances, essential oils, abrasives, oatmeal, spices) are added after the fats/lye/liquids are emulsified.
This is tracing, see 6 below.
- Prepare your soap mold by lining with wax paper (tape helps)
- Weigh all ingredients carefully (even liquids!) and set aside. Place the weighed lye into a sandwich bag.
- Place weighed liquids in a non-reactive container (Pyrex works fine), take it outdoors if possible, and gently pour the lye into the water being careful not to splash. Mix gently with spoon. Do not inhale the fumes! The mixture will get very HOT. Throw out the empty bag.
- Place fats/oils (not fragrance or essential oils though) in a pot and melt, then remove from heat.</p">
- Check the temperatures of both the melted fats and lye/water mix. When they are both as close to 100 degrees as you can get them (it may take a little juggling back and forth to get them to both the same temp at the same time), carefully pour the lye mixture into the pot of melted fats. Mix together with a non-reactive spoon.
- Blend with the hand mixer or blender for about 5 minutes, then stir by hand for 5 minutes, back and forth until "trace" is reached (the contents will thicken like pudding and eventually you will be able to make traces of the mixture onto itself. (See photo.) You can stir in your fragrances, etc. now.
- Pour/scrape the mixture into your mold. Wrap the mold with towels and keep for 24-48 hours in a temperate place.
- Pop the soap block out of the mold, peel off the wax paper and slice with your favorite cutting tool. Place bars of soap on a rack and let them air-cure for 4-6 weeks. You MUST do this since some lye will still be active. Bars may lighten in color over time.
Soap bars on a cookie rack for curing.
Enjoy! The printable recipe for my favorite moisturizing soap can be found here.
Deb Tejada is an urban farmer, foodie, do-it-yourselfer, graphic designer, illustrator and web developer living in sunny Colorado. When she’s not in the kitchen or garden, you can find her at The Herban Farmer. Read all of Deb's MOTHER EARTH NEWS posts here.
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