Converting an Existing Recipe to use a lower % of Alcohol.

You found the perfect Transparent soap recipe but it requires 190 Proof Grain Alcohol and all you can find is 150 Proof. Do not worry, there is a way to make it work. 190 Proof Alcohol is 95% Alcohol and 5% water. 150 Proof is 75% Alcohol and 25% water. What happens here is that you are introducing more water in the recipe when you are using the weaker Alcohol, so what you have to do is discount the water for the lye and the sugar solution in order to compensate. You also need to use more Alcohol because the one you are using is a weaker solution. Here is how you do it:

First divide .95 by .75 to find the multiplier. (.95/.75 = 1.26)

Let's say your recipe requires 10 oz of 190 Proof Alcohol, multiply 10 by 1.26 = 12.6, so you will need 12.6 oz of 150 Proof Alcohol.

Now let's address the excess water: If the requirements for the 95% Alcohol were 10 oz of alcohol, that means we are introducing .5 oz of water into the recipe. (10 x .05), but when we use 12.6oz of Alcohol at 75%, (12.6 x .25 = 3.15) we introduce 3.15 oz of water into the recipe. Substract .5 from 3.15, that means we have 2.65 oz of excess water.

Let's say that your recipe required 14 oz of water total (water for the sugar solution + the water for the lye), then substract 2.65 from 14 = 11.35, that means that you can use 11.35 oz of water in your recipe. I like to mix my lye with at least 1.5 times it's weight in water, let's say you need 4 oz of lye, then you would mix it with 6 oz of water. That keeps the soap soft enough after the gel stage so you can stir it. You are left with 11.35 - 6 oz = 5.35 oz of water for the sugar solution. You can round up those numbers, but use as little water as possible in the sugar solution, you do not have to use the whole amount.

Formulating your own Recipe

You can formulate your own recipe, you just have to follow a few rules. Not all CP recipes can make good transparent soap, some oils just won't work well when used to make clear soaps. The basic oils are Palm, Tallow, Lard, Coconut or Palm Kernel, and Castor oil. Olive oil and other soft oils can also be used. I have successfully used refined Shea Butter. You will have to experiment. Castor oil is fantastic in transparent soap because it is very conditioning but it also serves as a solvent. When formulating a recipe to use with a weak alcohol solution (140 - 150 Proof), your best bet is a higher percentage of Castor oil. Keep it between 30 -35% of your recipe. Too much of it will cause the soap to be too soft. If you are using Lard instead of Tallow or Palm, replace 1 oz per pound of Lard by Stearic acid, because Lard makes a softer soap and the Stearic acid will help in making it harder. If you use too much Coconut oil, you will get a cloudy soap, keep the % of Coconut oil around 20%. Do not use a lye discount when formulating for transparent soap, any oil that is not saponified will cloud your soap.

As I said before, read the book How to make Transparent soapby Catherine Failor in order to learn how to formulate your own recipe. She explains everything and she has a nice "troubleshooting" section that is very useful. She recommends using a 60% actual soap (Oils + lye)/40% solvents and a 50% actual soap/50% Solvent (solvents are: Total water including the water for the lye solution and the water for the sugar solution + Alcohol + glycerin, it does not take into accound the sugar itself) ratio in order to determine the quantity of solvent required to make the soap transparent. I made a calculator to help with this, because it takes a while and it gets complicated when you start calculating everything by hand. I made this calculator available to you, you can download it, it is a zipped file, once extracted, open it in Excell (do not activate the macros, they do not work anyway) and save it as a .xlt file, which automatically should put it in the Microsoft template folder. It will calculate recipes both for 190 Proof Alcohol and for 151 Proof Alcohol (150 Proof would be just about the same). If you are using 140 Proof Alcohol, email me and I will send you a version that will work for you. The calculator is easy to use, you use the recipe worksheet to formulate your recipe and the print sheet to print out a clear and concise recipe sheet that will look exactly like the Recipe page for the tutorial.

Once you have a recipe in the calculator, it will give you the solvent requirements for a 60/40 and a 50/50 solution. You can start by adding the quantities of solvents in the 60/40 column and then test and adjust the soap by adding solvents up to the numbers in the 50/50 column. Example, in the 60/40 column, the requirements for Alcohol are 12 oz and in the 50/50 column, the requirements are 14 oz. You can start by adding 12 oz of Alcohol in your soap, and if it is not transparent, then add the other 2 oz, an oz at a time, testing between each addition, same with the sugar and the glycerin. Take a lot of notes and write everything down, when you finally have a transparent sample, write down everything you added and all the quantities, this is your recipe, the next time, you will need very little adjustments in order to make the soap transparent.

I hope this helps and I hope you will give transparent soap a try, it is a lot of work but it is fun to make and it really is a fantastic soap, mild to the skin and makes tons of lather.

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