Not only is olive oil soap making an absolute blast of a craft, but it’s also extremely practical. Once you’ve “released those creative juices” and formed your work of art, you will have an amazing natural skin care product that can truly change your skin for the better.
So how exactly does olive oil soap making work? It’s really quite easy… You simply mix olive oil with a substance called lye (sodium hydroxide) to create a chemical reaction that produces soap.
OK, maybe this will take a bit of an explanation. In order to make soap, a chemical reaction called saponification absolutely must occur. During saponification, an acid reacts with a base to form a salt. The acid is your olive oil, the base is your lye, and the salt produced from this reaction is the all natural soap.
The key to making olive oil soap successfully is to use the correct amount of lye in the reaction. There needs to be enough lye to turn just about all the olive oil into soap and create a relatively hard bar but not so much that it makes your soap caustic and harsh.
So how do we know how much lye is needed for olive oil soap making? In order to find this out, you need to refer to an SAP value chart that will reveal the saponification value of olive oil. According to our chart, olive oil has a lye sap value of 135.3. This means that it takes exactly 135.3 milligrams of lye in order to completely saponify 1 gram (1000 milligrams) of olive oil.
If you divide each side by 1000, you’ll realize that it takes .1353 milligrams of lye in order to saponify 1 milligram of olive oil. Now that both ingredients are represented in the same unit of measurement, you can take the weight of the olive oil being used in the recipe and multiply it by .1353 to find out the weight of the lye needed.
Here’s a quick example to clear up any confusion: How much lye would you need to use in order to saponify 7 pounds of olive oil? To figure this out, just take 135.3 (olive oil’s SAP value)/1000 x 7 pounds of olive oil. As you can see, in order to completely saponify 7 pounds of olive oil, you would need .9471 pounds of lye.
In reality, you do not really want to completely saponify all the oil. If you did, the results would definitely not be mild skin care soap. In order to create a mild cleansing bar, you must apply a discount to your lye measurement so that some of the oil will remain within the soap unsaponified for skin care benefits. This, by the way, is called superfatting.
For olive oil, I recommend a 15% discount; meaning 15% of the olive oil will not interact with the lye to make soap. This will ensure that too much lye is never used and that some olive oil will remain unadulterated within the finished product.
In order to apply a 15% discount, just multiply the weight of the lye needed to completely saponify an oil by 85%. For example, to find out how much lye we would actually use with a 15% discount in our example above we would multiply .9471 pounds by 85%.
Keep in mind that even for olive oil soap making you will never use olive oil alone. Multiple oils are absolutely required in order to create soap successfully as each one has it’s own characteristics that supplements the detriments of other ingredients.
Using olive oil alone would create a very soft bar of soap that has a slimy lather and spoils quickly. If you add a percentage of palm oil for hardness, and coconut oil for a better lather, you are well on your way to creating a masterpiece.
Olive Oil Soap Making – Simple Steps for Success