Tuesday, February 25, 2014

Hot Process Soap

If you have the option of doing something complicated or doing something easy, when the end result is the same, what do you choose? The more and more we do around the homestead, the more we are looking for methods to simplify things.

Dara and I have been making cold process soap for many years now. Making cold process soap is easy once you understand the basics, I encourage anyone interested in making it to go for it, here is a post on how. But, it is also a little technical when it comes to temperature. You have to bring your oils up to a specific temperature while simultaneously bringing down you water/lye mixture temperature. They need to both be about 105 F to 110 F when you mix them. We have discovered an easier, less technical way of making soap and get this, you can use it in a couple days instead of 3-4 weeks.

Make sure you wear the proper safety gear when making soap. Use gloves and eye protection always. Bad Dara!

When I heard of hot process soap making, in my ignorance, I just assumed it was the cheater way of doing things, and that making cold process soap was the pure way of doing things. I thought it was akin to extract brewing versus all grain brewing, yeah I said it. Thanks to our friends Heather and Mike, we learned that hot process is just a faster, easier way of making soap using almost all the same techniques.

Disclaimer : Making soap involves handling lye (sodium hydroxide) which is a very strong alkali that is water soluble. When water is mixed with lye it creates a very caustic basic solution. This means it will seriously burn your skin, eyes or lungs if handled improperly. Please do your own research before you make soap. This post is for informational purposes only, not a 'how to' make your own soap.

Here is the quick and dirty of making hot process soap:
  • Use any cold process recipe you have. Soapcalc is a great resource for making your own recipes.
  • Melt your fats on high in a crock pot large enough for the full recipe with room to mix.
  • Once your fats are melted and mixed, add your water/lye mixture to the fats. Another quick Disclaimer: Always add your lye to the water not water to the lye. Never use metal containers to mix your lye in. Use a glass or plastic Tupperware container or pitcher.
  • Mix the fats and lye/water mixture with an immersion mixer until you hit a light trace. Trace will happen faster in the process due to the higher heats.
  • Once you hit trace leave the crock pot on high and mix the soap every couple of minutes to keep it from burning or sticking to the crock.
  • In a short period of time the soap will have a "mashed potato" consistency. Continue mixing the soap every couple of minutes until the soap starts turning translucent. 
  • Once the soap is in the "gel phase" or translucent you can add your adjuncts like coloring and essential oils.
  • Mix in any adjuncts and spoon into your mold. 
Something else to consider is the flash point of the essential oil you are using. Some oils have a very low flash point, like eucalyptus, which will vaporize at 109 degrees Fahrenheit. If you are using a low flash point essential oil you will have to wait until the batch cools down under the flash point before you mix it in. Here is a good website with the flash points of common essential oils. 

Most of the saponification has already occurred in the crock pot. The high temperatures speed up the saponification process. You are suppose to be able to use the soap in 24 hours. I say once the soap hardens, about 24 hours later, take it out of the mold and cut it. Let the bars cure for a few days at least to harden, or they will melt faster when you use them.

There is something very satisfying about dropping a giant soap log on wax paper...

And here is the final product. Dara put a bunch of spirulina in the large batch giving it a green color and a somewhat ocean like smell. I have been using it for a couple weeks now and it is great. I hope this inspires some of you to start making your own soap.  


  1. Super duper, thank you for the inspirational blog. I have been wanting to make my own soap for a couple of years and your post seems to have helped me go beyond my inertia. My goal is to make my first batch by the end of March 2014.
    Thanks again,

  2. Glad to hear it. Just be safe and wear the proper safety gear. Once you get a batch under your belt you will see how easy and superior homemade soap is to store bought.