But one of the things that sets our handmade natural soap apart is the soap maker's creative use of colors. Whether you make a bar with one solid color throughout, a standard swirl, a layered effect, or any number of other swirling/coloring techniques, it's your own personal touch that makes it wonderful.
Part of what attracts people to making their own soap, however, is being able to make it as naturally as possible. Lucky for them, there are many different choices of natural colors to use in making soap. Most colorants are just added at trace, but there are some that work best if they are infused into the base oils before making the soap. Here is information on how to use four of my favorites, with instructions how to use them, and links to examples of what they look like in the finished soap.
Generally, there are two methods of infusing the botanicals into the oil:
- cold infusion - adding the botanical to the oil and just letting it sit for a few weeks, shaking/stirring every few days (a sunny kitchen window is great for doing this)
- warm infusion - where you add heat either in a crock pot or warm water bath. This method infuses the color in just a few hours. (How to make an herbal oil infusion.)
1. Alkanet Root
- at trace - add up to 1/2 tsp. per pound of oils - but beware, it is really hard to incorporate and tends to give a speckled look
- infused in the base oil - works much better and gives a more even color.
In a mason jar, add about 1 tbsp. to 1 cup of olive oil. Stir it well and let it sit for a week or two, shaking the jar every couple days or so. After the color has been infused into the oil, pour the oil through a coffee filter or strainer to get the leftover powder out. Then use the oil in your soap recipes as you normally would. Depending on the amount of olive oil in my recipe, I'll use half to all of the infused oil as the olive oil in my recipe. This results in between 15-30% of the total oils in the recipe being the colored/infused oil.
Note - as the soap cures, the color will change. This is due to the colorant being sensitive to the changes in pH.
2. Annatto Seeds
To get the nice yellow/orange color, you need to infuse the seeds in your oil using either the warm or the cold method.
Use 1 tsp. of seeds in 16 oz. of oil to get a nice pale yellow. Use 2 tsp. for a richer, darker color. Strain the annatto seeds out before using the oil in your soap. Depending on how strong an infusion I've made, I generally will only use annatto oil for half of my olive oil - it's a pretty strong colorant.
For the soap pictured here I made a half batch with normal olive oil, and a half batch with annatto infused oil, and then swirled the two batches together (with some poppy seeds, a wonderful natural exfoliant)
To infuse the oil, steep it in your olive oil just like the alkanet - about 2 tbsp per cup of olive oil. Let it sit for 1-2 weeks and strain out the powder before using.