Let’s Make Soap!
Crafting soap at home can be rewarding, particularly if you like experimenting with kitchen chemistry.
By Oscar H. Will III | Photos By ©iStock.com / Vitaliy_ph
Once you master the technique below, search online for hundreds of additional recipes. If you make changes, be sure to run them through this online lye calculator (https://www.brambleberry.com/Pages/Lye-Calculator.aspx) to get the proportions right.
- Long-sleeved shirt and apron
- Digital kitchen scale
- Rubber gloves and safety goggles
- Digital thermometer with probe
- Immersion blender (hand blender or stick blender)
- Large styrene plastic or silicone spatula
- Stainless saucepan
- Glass or metal baking pan sufficiently wide for the stainless saucepan to sit flat in it
- Several glass liquid measuring cups
- Glass bowls, a 1-cup and a 2-cup are suggested
- 1.5-quart glass baking dish or other suitable mold for your soap (plastic food-storage boxes, sour-cream cartons or purchased soap mold. You will slice the soap once it’s hardened in the mold.)
- Sharp knife
- Cooling rack
- Paper towels
- pH strips with a value range from 8 to at least 14
- 450 grams olive pomace oil
- 150 grams coconut oil
- 87 grams lye (Always use 100% sodium hydroxide or lye in crystal form. Don’t substitute liquid lye or drain cleaners.)
- 198 grams distilled water
Editor’s note: When making soap, use equipment that will not be used for cooking. Also, don’t use copper, tin or aluminum for the saucepan, as they will react with lye.
Steps for Making Soap At Home
It is quite easy to make a simple farm-style lye soap using this basic recipe. Once your skills develop, you can add garden herbs, essential oils or other scents, and various colorings. You can even make a hand soap suitable for the farm shop by adding ground charcoal to your next batch.
Soapmaking involves a chemical process called saponification, which converts fats and the highly caustic base, lye (sodium hydroxide), in your recipe into soap. Since you will be working with lye, you’ll need to exercise caution, as it can burn your skin and sufficiently damage your eyes (even blind you) should you get a concentrated amount in them. Soapmaking is not dangerous per se, but you want to be sure that you work carefully and safely using the protective gear listed. Work under your stove’s hood if it vents to the outdoors. If it doesn’t vent outside, you should work outdoors or in another well-ventilated area.
1. Don gloves, apron and goggles, and turn on your hood’s fan. Again, if the hood does not vent to the outdoors, make your soap outside or in another well-vented area.
2. Working on the counter, carefully measure out all ingredients by setting the measuring cup on the scale, hitting the zero button, then adding the ingredient to the specified weight.
3. Place both oils in the glass bowl, the lye in a small measuring cup and the distilled water in the stainless saucepan.
4. Microwave the oils to melt if they are solid, but try not to heat them beyond 100ºF.
5. Under the hood, slowly add the lye to the distilled water, while stirring carefully with the spatula. Avoid inhaling the fumes. As the lye dissolves in the distilled water, the mixture will get quite hot; be careful here. And never add water to the lye—it can lead to a very dangerous and hot reaction.
6. Add a small amount of cold tap water to the baking pan that fits your saucepan. Then, carefully set the saucepan in the water. Measure the temperature of the lye solution, and after each use, rinse the probe with copious amounts of tap water to dilute the lye solution that sticks to it. You may need to add some ice to the water in the baking dish to help the lye solution cool faster to the target of between 90º to 100ºF. Once at the correct temperature, remove the saucepan from the baking dish.
7. Add the melted (90º to 100ºF ) oil mixture to the lye, stirring with the spatula until the lye solution and oil are fully mixed.
8. Place your saucepan in the sink, and carefully blend the contents with your immersion blender (keep the head on the bottom of the pan, and move it around without tilting to avoid spraying the mixture outside of the pan) until it has the consistency of a loose custard or mayonnaise.
9. Pour the slightly thickened mixture into the baking dish or other container you designated as the mold.
10. Cover your mold with plastic wrap, a towel, cardboard or a fitted lid, and set it aside for at least 24 hours. If you use a towel or other cloth, you will help drive the saponification reaction to completion by conserving heat.
11. After 24 hours, check the soap to see if it is hard enough to easily remove from the mold in one piece. If it doesn’t want to come out, give it another day. If it is hard and still unwilling to come out of the mold, place it in the freezer for an hour or so, and then remove the soap.
12. With a knife, cut the soap into bars of a size and shape you like.
13. Place the bars on edge on the cooling rack in a cool, dry place out of the way to cure for at least a month (longer is better) before testing and using.
To test your soap after a month, you can wet it and rub it on your arm gently, then watch for any redness, a sign of still too-high pH. Alternatively, you can wet it with distilled water and place a pH test strip on it. The strip should indicate a pH of 9 to 10. If it is higher than that, you can let it cure longer and retest. If it is slightly lower than that, no problem.
Store your bars in a relatively cool and dry location in open plastic, wooden or wicker containers. You can cover with a cloth, but for best quality, your stored soap should be able to breathe.