Soapy Science: Jojoba Oil



I have been asked some questions about the use of Jojoba oil in soap making lately, so I thought I would address it in better detail in a post for all to read. After reading The Ultimate Guide to Hot Process Soap, you know that oils are primarily comprised of triglycerides which are made up of one glycerol and three fatty acids. Although many call the liquid extracted from the Jojoba seed Jojoba “oil”, it’s actually not an oil; it’s a polyunsaturated liquid wax. Instead of having a chemical composition made up of primarily triglycerides, it’s actually comprised of fatty acids and esters composed entirely of straight chain alcohols.



What is an ester? An ester is a chemical compound derived from an acid (organic or inorganic) in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group. In jojoba wax, both the acid and ester alcohol portions have 20 or 22 carbon atoms, and each has one unsaturated bond. The unsaturated fatty acids allow it to look like a liquid, instead of a solid, like other waxes that may come to mind, such as beeswax or soy wax. Jojoba wax does not oxidize, it does not become rancid and it does not break down under high temperatures or pressure. This gives it an incredibly long shelf life and will not cause DOS in your soaps.



Take a look at the images below, notice the differences between a molecule of sunflower oil and a jojoba wax molecule? The sunflower molecule has one glycerol bonded to three fatty acids. The jojoba wax molecule has one fatty acid bonded to an alcohol.



Jojoba Wax

Sunflower Oil



We know that the saponification of an oil molecule made up of a triglyceride requires three molecules of NaOH to break down the strong bond between the glycerol molecule and fatty acids. This will result in three soap molecules and glycerin. Review the chemical formula for saponification below.

Oil + 3 NaOH = Glycerin + 3 Soap (Each oil molecule requires 3 NaOH)


Ok, so if Jojoba wax isn’t really an oil, and it is instead made up of a fatty acid and an alcohol, what does this mean in regards to soap making? Because there aren’t three bonds that need to be broken (there is only one), only one molecule of NaOH is required. When the NaOH breaks the bond, you are left with a fatty acid (most often gondoic acid) and a super-long-name alcohol. The fatty acid saponifies, but the alcohol does not. We are instead left with an alcohol in our soap that provides us with a great benefit: long-lasting, big, full bubbles! The alcohol provides superior stability to lather, which can literally make your bubbles last for hours, although I don’t see any purpose for hour-long lather. This is the primary reason why I suggest adding jojoba oil to your recipe, rather than after (although you can certainly use it as a PCSF as well).



If you have the ability, I recommend doing an UG2HP experiment for yourself. Create a small sample bar of soap from purely jojoba wax. It won’t have all of the benefits of a combined informed recipe, but you will be able to see the effects it has on lather. Wet the sample bar, create lots of lather and put it in a clear plastic cup or on the counter. See how long the bubbles last compared to other soaps.



Although jojoba wax has been used for hundreds of years for its many benefits, unfortunately, the jojoba plant is slow growing and it is difficult to cultivate in large scale applications. This difficulty leads to increased costs for both the manufacturer and for consumers. At WSP, Jojoba oil sells for $27.95 for 16oz. With a price like that, one might ask, how do I use jojoba oil without breaking the bank? First, jojoba wax comes in different grades, which can affect the pricing. The highest quality is pure golden jojoba oil, but there are also refined, deodorized and distilled versions as well. I recommend only using 5-10% jojoba oil for extra lather stability and larger bubbles. What about other substitutes? A great substitution for jojoba wax is cetyl alcohol which is selling for only $3.95 for 16oz (WS). Because cetyl alcohol doesn’t have a fatty acid bond, it will not be saponified and can be melted and added after trace or near the end of the cook at a suggest usage rate of 3-5%. Other substitutes include cetyl esters and behenyl alcohol.



Questions? Do you use Jojoba Oil in your recipes? Share your comments below!