Metaphor Organic Soap

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Getting the Base Oils Just Right

Errol DavisComment

A common question is “what do you make soap out of?” The quick answer is “fat and lye.” Lye deserves a post all on its own, so today I’m just going to talk about the fats or oils. Firstly, we need to distinguish between fragrance or essential oils and base oils. Base oils are what most of the soap is made out of. Fragrance or essential oils are only about 3% of the soap, and they are added at the end of the process so the soap smells good. You can have soap made out of base oils with no essential oils but not the other way around. So, ironically, “essential” oils are not essential to soapmaking, haha.

We use vegetable oils for our base oils.

Note: on a lot of ingredient labels, when they say “vegetable oil,” they mean soybean oil. We do not use soybean oil. What I mean by “vegetable oil” is fat that is not from animals. We use plant-based oils because a lot of our customers don’t like products made out of animals. We also want to keep our manufacturing process as off-the-grid as possible. When you think about just the resources required, making soap out of animals doesn’t make a lot of sense.

Different base oils give different qualities to the soap.

This is one of the most interesting parts of soapmaking. You can’t just use any old oil and hope it will turn out right. Only certain fats will turn into soap in such a way that the soap is significantly cleansing. The most common oil that adds cleansing properties to a bar of soap is coconut oil, and another is palm kernel oil.

Coconut oil is great, but by itself, it is actually TOO cleansing. A pure coconut oil soap would suck all the moisture out of your skin. So you need to add a moisturizing oil to the recipe. Most plant-based unsaturated oils contribute moisturizing qualities to a bar of soap. Grapeseed oil, avocado oil, and apricot kernel oil are some examples of moisturizing oils.

The final important quality to mention is the firmness of the soap bar. Coconut oil on its own produces a firm soap bar, while any number of the moisturizing oils would produce a soft, mushy soap bar if they were the only ingredient. So, you need a third oil to add to the mix that adds firmness to the bar but that doesn’t add much cleansing effect. The oil that serves this function in our recipe is palm oil.

The Goldilocks of a base oil recipe.

Now you see why I said in the title that the oils need to be “just right.” There are actually even more variables that go into soapmaking, such as how much lather the bar produces, and how creamy and/or foamy the lather is. There is a great tool online that lets you calculate a lot of this stuff, which is available here:

There are also oils that don’t follow all the rules, such as one mysterious oil that you can use to make soap completely on its own. I’ll write a blog post on this one soon. Unitl then, you’ll just have to wait!