Though you can make soap using only one oil, the best soap recipes have a balance of oils. Soapmaking oils each have different fatty acid makeups. The percentage of each of the fatty acids in the oil determines how each oil will contribute a different quality to the final bar of soap. Generally, the qualities can be categorized in four ways:
Hard, stable, long-lasting: (palm oil, beef tallow, lard), these oils give a stable, creamy, low lather Lathering: (coconut, castor, palm kernel), these oils give bubbly, fluffy lather Moisturizing/Conditioning: (olive oil, canola, sunflower, soybean), these oils give a low creamy, milky lather Luxury/Super Moisturizing: (cocoa butter, shea butter, almond oil, hemp oil, jojoba), too much of these oils can dampen the lather—but they sure are good for your skin—they also help make the bars harder (they contain some of the same fatty acids that the “hard” oils have.
Many oils will have multiple characteristics, for example, shea butter is super moisturizing and makes a very hard bar of soap as well. Coconut is primarily used because it makes a great lather but makes a super hard bar too. Tallow is primarily used as a base oil (hard), but it makes really creamy, moisturizing lather.
Balanced Recipes With Different Types of Oils
A basic balanced recipe should have some of at least the first three oil categories—hard, lathering, and moisturizing. So a basic recipe could be:
30% tallow25% coconut oil45% olive oil
That would be a great, balanced basic bar of soap. Now, if you wanted to use only vegetable oils, you could use:
25% palm oil25% coconut oil25% olive oil15% canola oil10% sunflower oil
This is a great, basic recipe for soap. Many soapers also swear by adding 4-6% castor oil to their recipes. It increases the lather and gives the soap a nice creaminess. So … an even better, basic recipe for soap would be:
25% palm oil25% coconut oil25% olive oil10% canola oil10% sunflower oil5% castor oil
See how it’s balanced with a combination of hard, lathering and moisturizing oils? After you have decided on a balance of oils, you just need to run your combination of oils through a lye calculator of your choice and you’re ready to go. Don’t be afraid to experiment. Share your experiences with others in the soap making community. Take good notes in your soap notebook, and above all, keep on soaping!
