Infusing oil is probably my favorite method of using natural colorants. It works for most natural colorants but we’ll talk about the ones that do better using a different method as we go along. When you infuse oil you don’t get the grainy speckled look you get when you add spice or herb powders to traced soap.
You want to be sure to use a long shelf life oil for infusing. The top three are fractionated coconut oil, jojoba oil and olive oil. I usually stick with olive oil as all of my soap recipes contain olive oil.
There are two main methods of infusing oils.
Cold infusion –Add spices or herbs to the oil in a jar and allow to sit 2-6 weeks to infuse. If I’m infusing powdered spices or herbs I infuse 2 tablespoons in 5 oz oil. If I am using dry whole herbs then I’ll fill the jar with the herb and cover with oil. Never use fresh herbs in cold infusions as they contain water and will cause mold and bacteria to grow.
Heat infusion –Add spices or herbs to the oil and heat gently to kick start the infusion. Some spices and herbs infuse easily using the heat infusion method and you can even use the infusion the same day! You can heat using the crock pot turned to warm for 2-6 hours or low heat on the stove for 2-6 hours. You can use fresh herbs in a heat infusion if you plan on using the oil in soap making the same day. Don’t ever store away an infusion made with fresh herbs as they contain water and your infusion will grow bacteria and mold.
My favorite method is to use a hot water bath to gently heat the infusions. I seal the herbs and spices in heat sealable tea bags so I don’t have to worry about straining the infusion before I use it. I just simply remove the tea bag. Here’s how I do it.
I usually infuse 2 tablespoons of any powdered herb or spice into 5 ounces of olive oil.
Step 1 – Measure out 2 tablespoons of your powdered herb into a heat sealable tea bag.
Step 2 – Seal the edge with an iron. Make sure it is sealed and will not come open.
Step 3 – Place the sealed teabag into the canning jar and cover with 5 oz (weight) of olive oil.
Step 4 – Screw on the lid and secure tightly. If you’re doing many infusions at once make sure you label them so you don’t forget what they are. I just use a permanent marker on the lid.
Step 5 – Place your jars into a pan. Fill the pan with enough water to reach about 1” underneath the lid. You want the water to stay plenty beneath the bottom of the jar lids.
Step 6 – Turn the heat on low and let heat for about two hours. You can also do this in a crock pot. Just set the crock pot on warm.
Step 7 – Remove the jars from the pan and allow them to cool away from cool air or drafts. You don’t want the jars to break. I typically put my jars on the counter and cover with a towel to keep out the drafts or air if it kicks on. Check the color of your infusions. Some herbs and spices infuse easier than others. I noticed the alkanet, paprika, indigo, turmeric and annatto all looked nice and dark. But some of the others looked like they needed a bit more time. You can either heat for another hour or two or if you aren’t in a hurry to use them…let them sit somewhere out of the way for a week to get a darker infusion.
That’s it! Wasn’t that easy? And the best part is that since we used the tea bags to contain the spices and herbs we don’t have to bother with straining which can be a mess!
To use your infused oils simply replace a portion of olive oil in a recipe with infused olive oil. We’ll go into more detail later on in the series.