How I Made Homemade Soap (and Didn’t Screw it up)

I’ve attempted this before, but it didn’t work out so well.  You can see the finished, botched soap in this post. 

This time, things worked out much better.  Just like the first time, I started with bacon fat.  

Upcycling this dirty old jar of grease.

 And, just like last time, I washed the fat.  However, this time I decided to use only one jar of fat instead of two.  This helped speed the process up measurably.   I washed the fat twice just like last time to get out all the residual bacon bits.  

What I knew this time that I didn’t know the first go round is that washing the fat takes longer than any other step in the process.  You can save yourself a lot of time in your soap making by using other fats that are already clean.  Olive oil comes to mind.  So does coconut.  You can even find directions on the internet for Crisco based soaps.  For now I’m sticking with bacon fat because I always seem to have some around and I don’t have to buy it.  Someday I would like to try an olive oil (castille) soap but I’m going to refine my skills with bacon grease first. 

Washing the fat is the longest step in the process.

Now that you’ve washed your fat, it’s time to actually make some soap.  My directions from the first experience were pretty thorough, but I learned a few things along the way so I’ve added those golden nuggets of wisdom so that you don’t make the same mistakes I did.  

1. Clear your workspace of young children and pets.  Lye is not dangerous if you respect it and follow safe handling precautions, but children and chemicals don’t mix.
2. Weigh and melt the fat. 
   

   The fat liquified and ready to be made into soap.

   THIS IS VERY IMPORTANT.  Inaccurately measuring my ingredients was the biggest mistake I made the first time I made soap.  I used too much lye and the result was a chalky, crumbly soap.   This time I got a more accurate kitchen scale.  I want this fancy-shmancy one but I’m not willing to spend that much money on it.  I found a used one for $60 but I wasn’t ready to spend that much either.  We’ll see how much soap I actually make before I start forking out the big bucks on equipment.  My new kitchen scale cost $1 at the Women’s Resource Center.  It seems to work just fine for what I need. 

3. Once the fat is melted, use this lye calculator to determine how much lye you will need. 
   

   The mass of the water only; I set the scale at zero with the measuring cup on it.

   It will tell you how much water and lye you need based on the type and mass of fat you have.  It will even let you use multiple types of fat so that when you become a soap expert you can create new recipes. 

4. Once you have calculated how much lye and water you need, sprinkle the lye into the water IN A HEAT-PROOF GLASS CONTAINER and swirl with a silicone or rubber spatula.  (This is an exothermic reaction and gives off A LOT of heat; use caution.)  This is where I made my second mistake the first time I made soap.  I knew the lye mixture would be hot.  I knew it needed to cool.  I just wasn’t sure how much it needed to cool. 
   

   The lye-water solution has cooled to about 82 degrees.

   I talked to my soap-maker friends and learned that the temperature of both the lye-mixture and the fat are critical to the finished product.  Here the lye has cooled enough to combine with the fat.  It is just over 80 degrees.  The fat should be about the same temperature; warm enough to be liquid, but not too hot.  If your fat and lye solution are too warm, the resulting soap can be brittle.  (Like mine was last time.) 

5. Once the fat and lye are both under 100 degrees slowly and carefully pour the lye solution into the fat and stir continuously with a stick blender.
   

   Stir the mixture constantly once you have added the lye.

   It will take quite a while for the mixture to thicken up to the right consistency.  (Especially if you have measured your ingredients correctly; my soap reached trace really quickly the first time because I used too much lye.)  Don’t stop stirring even when your arm gets tired.  The soap is finished when it reaches “trace”.  Trace is when you can see where you have been mixing.  In the photo you can just see the path where the blender was.  

   

   The soap is ready when you can see where you were just mixing. This is called "trace".

   And, in the sake of complete disclosure, this photo is from the last batch of soap; the picture of trace from this batch wasn’t so great.  If you are going to add fragrances or herbs, now is the time to do it.  Last time I added dried lavender blossoms.  That was a waste of perfectly good lavender blossoms.  They turned brown in the process instead of being lovely little purple flecks like I’d imagined.  This time I stuck with straight essential oils.  I’m particularly fond of lavender in my soap so of course, I used that but I added lemongrass again too.  

   

   Lavender and lemongrass essential oils.

   I didn’t add enough oil this time so the soap is only slightly scented.  Next time I will add much more.  One of the reasons I like homemade soaps (both mine and Fish Creek’s ) is that they make the bathroom smell lovely instead of all soap-y like commercial soaps.  The last time I opened a bar of store soap, it about made me gag.  It’s amazing how artificial artificial fragrances smell when you get used to smelling real smells again. 

6. My friend Alicia keeps me in soap molds. 
   

   Upcycling trash into treasure.

   She provided the silk container (which wasn’t big enough for two jars of bacon fat-soap last time) and this giant Goldfish container (which was actually too big for only one jar of bacon fat this time).   Once you have blended in any fragrances you want to add, pour the liquid soap into the mold and let it cure for 18-24 hours. 

   

   Finished soap in my fancy soap mold.

   Once the soap has cured for a day, you can remove the soap from the mold.  Or, if you upcycle an old container like I did, you can just peel the mold off of the soap and discard it.  I forgot to take a picture of the soap before I started cutting it, so I had to push it back together to provide you the illusion of “whole-ness”:  You get the idea.

7. After you’ve cut your block of soap into bars, all you have to do is wait.  Soap needs to cure for awhile.  At least three weeks is recommended, but the bars will get harder and drier with age. 

The freshly cut bars biding their time.

So, I haven’t used the bars yet but they cut smoothly and didn’t crumble or get chalky like the last batch so I’m assuming all’s well for now.  They seem to be curing nicely and will be ready for use soon.  Now that I’ve figured out the process, I think I’m ready to start playing with some recipes.  Like maybe this one.