2011-12-25 Against SOPA or How To Do Soap
I'm against SOPA... So I'll explain how to make soap with olive oil
One more time, some lobbyists try to regulate the Internet with some of the stupidest laws or rules. SOPA (in US) is again one of this tentative to break down the freedom of citizen worldwide to preserve some archaic business model. As I have a preference for concrete action leading to a direct social improvement, I'll explain how to do soap (it's better than SOPA and more useful, please note the clever inversion of the letters). My soap recipe is released under the public domain dedication license (CC0).
Doing soap is a chemical process that requires your full operating brain. Especially that you'll use sodium hydroxide that is a corrosive substance. So respect the proportions, the process and read the whole process multiple times before doing it. Wearing protective gloves and goggles is highly recommended. Avoid to use kitchen instruments in aluminum as it will be attacked by the sodium hydroxide.
Background of the chemical process
Doing soap is one of the first chemical process discovered by the humanity. The process is called saponification that is done by using a base to hydrolyze the triglycerides contained in the fats (organic or animal). This process generates a fatty acid salt along with the glycerol (the greasy touch of the soap). Each fat has a specific value for its saponification. The saponification value (usually called SAP in saponification tables) is expressed by the required volume of base (usually sodium hydroxide) to saponify 1 gram of fat. The saponification value is reduced to keep the resulting soap a bit fat (what is called the "excess fat"). I find it even convenient to keep a "safety" bound to ensure that the hydrolyze is complete and used the whole sodium hydroxide.
So that's the basis if you want to build your own soap, there are other rules to consider but for this recipe this is enough. In my case, I use olive oil as a fat. Easy to find and I have a preference for organic olive oil (to ensure that the oil producer is taking care of its environment). But you can use non-organic olive oil too (it's usually cheaper).
- 1000 grams of olive oil
- 124 grams of pure sodium hydroxide / NaOH (as the olive oil has a SAP factor of 0.134 and we want 7% of over fat → run bc and type (1000*0.134)*0.930) (total weight of fat *SAP factor for the fat)*(0.900<->0.960))
- 350 grams of tap water (usually between 31% and 35% of the total fat. In this recipe ~ 1000*0.350)
- Put your protective gloves and goggles
- Prepare the sodium hydroxide by putting the sodium hydroxide in water (!put the sodium hydroxide in water not the reverse!).
- and monitor the temperature of the prepared sodium hydroxide to reach around 46-47 Celcius degree (it will start at 80 Celcius degree with the reaction).
- At the same time, warm the olive oil until 46-47 Celcius degree.
- When both are at the same temperature (around 46-47 Celcius degree),
- you can start to mix (using a mixer speed up the process) the warmed olive oil by incorporating the prepared sodium hydroxide. (!use a large pot to avoid projection of the prepared sodium hydroxide while mixing!).
- When you start to see that the mixture is becoming consistent (especially that you can see a trace while removing the mixer) it means that's you reach the critical point.
- When you have an homogeneous consistence, you can put the result into a plate.
- Put a plastic film into the plate touching the mixture (to avoid oxygen to be in contact with the prepared soap).
- In the next hours, you'll the "gelification process" where the soap is becoming a gel (usually starting from the center).
- After 24 hours, your soap is becoming harder. (see above picture)
- You can can remove it from the plate and cut the forms you want from your block soap.
- And the soap must dry for the next 4 weeks in a dry and clean place. (see above picture)