Soap can be made from just about any kind of fat. Even though fat from bacon, called lard, isn't the finest of fats to use for making soap, it somehow seemed to be the most exciting. Why? Because bacon is amazing. It has an almost mystical power to it and is a food that can be craved to almost no end. I figured what better way use the extra grease I had from cooking bacon then to turn it into soap!
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Step 1: Find Bacon Fat
You can get bacon fat from a variety of sources. I got my bacon fat from working as a white water rafting guide over the summer. Day three of a five day rafting trip means bacon for breakfast, lots of it. I collected the rendered fat in plastic water bottles with the original intention of using the grease to make a bacon fat bomb - basically a concentrated grease fire, but what didn't get used to make grease bombs followed me home and sat on the shelf for a while. After cooking bacon a few times in my house, I had a little more than a quart of rendered bacon fat ready to go.
You can render your own bacon fat by just cooking bacon - I would cook up at least 10 pounds of bacon if you want to render enough fat to make a sizable batch of soap (my one liter of fat came from around 10 pounds of bacon and yielded about a dozen bacon soap strips and about another dozen small to medium sized bars. You can cook less bacon if you want to make less soap.
The fattier the bacon you buy for this the better results you will have. Also, cooking it on the stove in a pan is going to be the way to go here - don't try any microwave tricks, you won't render nearly as much fat. Don't worry if lots of black and brown bacon bits get into your rendered fat, they can be purified out later.
You can also buy lard directly at the grocery store - although something about just buying the lard without the bacon seemed to be like cheating when doing something as epic as turning bacon into soap, but if you want to save some time and money - buying the lard direct would be the way to go.
***Note: I have found that a good way to clean dirty bacon fry pans is to pour old coffee grounds into the pan (this was taught to me on the river), let it sit for a bout half an hour and then do some scrubbing. The blackened crud on the bottom of the pan comes off much easier this way than if you try to attack it head on.***
If you're going to be saving your bacon fat over any length of time, get yourself a nice big plastic or glass jar. Remember to let the fat cool a little before pouring it into your container so you don't crack or melt it.
Step 2: Gather the Other Materials
Once you have your fat collected you can move on to assembling what you will need to make the soap.
1. Rendered fat - about 1 liter of it if you want to make about two dozen small bars/shapes of soap
2. Bacon Molds - I used candy molds of bacon and eggs, I couldn't find molds of just bacon. The molds I used were ok - not great, but certainly recognizable as bacon. Ultimately it would be nice to cast some high quality molds of a couple of good looking bacon slices to use for projects. I bought the molds from an ebay seller who sells lots of plastic candy molds (search for "bacon" in the search bar and you'll find them).
3. Household Lye - which is sodium hydroxide and the main ingredient in drain cleaner. It's what turns the fat into soap. This is done through a process called saponification, I'll explain more about this process later. You basically just want 100% pure lye - no additives, no Draino stuff, just good old fashioned lye. Lye used to be used for all kinds of things but it's getting harder to find these days as hardware stores become more reluctant to selling it. I got mine an old time hardware store, but if yours doesn't have it you can order lye online from any soap making supply company. Check out the wikipedia article for some background info on this magical powder.
4. Non-metallic bowls and utensils - you don't want to bring the lye into contact with metals, so find a plastic or glass mixing bowl to do your soap mixing in and some wooden or plastic spoons to stir it with.
5. Measuring cup - you need this to measure how much fat and water you have so you can mix in the correct amount of lye.
6. Bacon Bits - these bacon bits were bought at the supermarket and are ironically vegan. No bacon here, but they do have some nice bacon aroma which I thought would flavor the soap nicely and act as an exfoliant on skin.
7. Safety goggles and gloves - the lye can cause some pretty nasty chemical burns if you get it on your skin, so handle it with care and wear the appropriate coverings. It's not super volatile, you just don't want to touch it. If you do happen to get some on you, you can neutralize the chemical burn with an acid - like vinegar. I learned this from fight club - but it's actually true.
8. Dye or food coloring - I used just regular red and yellow food coloring to dye my soap in order to make a more realistic slice of bacon. Substitute any food safe dye here to get the colors that you want.
9. Saran Wrap - you will need some to cover the soap as it cures.
10. Scale to measure the lye (not pictured here) - you will need some kind of accurate way to measure the lye. I did weighed my lye using a digital scale, but volumetric conversions can work if you want to use measuring spoons to get around this.
11. Power mixer (not pictured here) - this really helped speed up the mixing process and I would recommend it it if your soap mixture isn't thickening as your mix it.
Once you have assembled these items your ready to get started on thinking about your recipe.
Step 3: Background and Recipe
To make soap out of the bacon fat it's useful to understand a little bit about whats going on. To make soap you need just three ingredients - some kind of pure fat, water, and lye. The lye chemically turns the fat into soap through a process called saponification. Thats when the triglyceride molecules in the fat bond with the sodium hydroxide molecules (lye) and form 1 new soap molecule and a glycerin molecule. You can check out James Hershberger's chemical explanation of saponification to learn more.
Having the right amount of lye is important. Too much lye and you will have extra left over in your soap when the chemical process is complete - this will mean your soap will have lye in it when it's done curing and it could burn your skin. Too little lye and your soap will have some actual fat left in it and instead of cleaning you, it will just grease you up. Most soap makers add too much fat to their soaps on purpose (a process called superfatting) because having a little extra fat in soap actually makes it feel quite nice.
The soap recipe I used was taken from Walton Feed's soap making page. I used a modified version of the basic hand soap recipe that had some small changes made to it based on the information on the useful lye to fat ratio table. I modified the original recipe because I wanted to superfat my soap.
I had 32 ounces of pure lard so I started from there. In order to get a desired excess fat of 5 percent in my finished soap the table called for multiplying the amount of fat I was using by 0.132 in order to figure out how much lye I should use. 32 ounces x 0.132 = 4.224 (roughly 4.2 ounces of lye). Most of the recipes I saw for basic soap used approximately 1/2 water as much water as fat in their recipes. Some call for slightly less water and some call for slightly more. I used 2 cups of water to my 4 cups of fat and it worked out well.
The basic bacon soap recipe is:
4 cups of liquid bacon fat
2 cups cool water
4.2 ounces of lye
3/4 container of bacon bits for exfoliant
15 drops of red food dye for bacon colorings
You can use this basic recipe as is or you can modify it in lots of ways - many of which are covered on Walton Feed's general instructions page. You can superfat your soap to whatever percentage of remaining fat you like, you can add in fragrances and you can add in special kinds of fats like coconut oil and olive oil to make the soap produce more bubbles than it does when using just straight lard (fat from pigs) or tallow (fat from cows).
Since I wanted my bacon soap to be as pure as possible, I just stuck with the basic recipe.
Step 4: Purify the Fat
The first thing you have got to do with the rendered bacon fat is to purify it. When it comes out of the bacon pan or storage jug or rendering pan it will most likely have lots of little bacon bits in it. We don't want any of those to get into the soap because they would most likely turn rancid at some point and mess up the curing process. To purify the fat you need to first warm it up slowly and get it boiling with a bunch of added water in a pot. I put my containers of fat into a hot water bath to melt the fat first so I could get the lard out of the containers and into my pot.
Once the fat was soft enough to pour/scrape out of the containers I added them into a big pot and mixed my fat (about 4 cups worth) with 8 cups of water. The fat shouldn't be boiled alone. Use about two times as much water as fat you would like to purify.
With the liquid bacon fat and water in the pot I then slowly heated the mixture and brought it to a slow boil (do this process gradually so it doesn't splatter everywhere). I let it simmer for a little more than an hour - at which point it reduced its volume significantly and visually appeared cleaner - although it didn't smell any better. Take the mixture off of the heat and transfer it to the refrigerator until it solidifies again.
(Check out the refrigerator the bacon fat is cooling in - have you ever seen so many veggies? I hope the bacon fat didn't feel self conscious in there.)
Once the fat solidifies (2-8 hours depending on how much fat you have and your fridge temp) you have to get the fat cake out of the pot and into yet another big pot. At this point your trying to pour just the fat into the new pot - leave the watery substance and the bacon bits that have separated to the bottom of the fat glob behind - you want just the pure fat cake thats sitting on top of your water and nasty bacon bits. I used my hands to do this as just pouring it into the new pot will prevent you touching the fat glob, but won't yield quality results.
Take the solidified purified fat and return it to the stove. You want to heat it up just so it turns into a liquid. Try not to make it too hot, it will be important to have it at the right temperature in the next step.
Sold, liquid, solid, liquid - make up your mind fat!
Step 5: Prepare the Ingredients
Now it's time to take that luke warm liquid bacon fat and measure out the correct amount - I started with about a liter of bacon fat so my 4 cup recipe used just about everything I had. The temperature of the fat was right around 105-110 degrees Fahrenheit - warm enough to keep it liquid, but not too hot for soap making. Cool or heat the fat in the fridge or on the stove as necessary to get your fat to a similar temperature.
To prepare the lye you need to dissolve it into water. My recipe called for 4.2 ounces of lye dissolved into 2 cups of water. I used cold water because I have read that it is better than room temperature water because there is less chance of fizzing up. Fizzing is bad since the lye can burn you if it touches you. With rubber gloves and proper eye protection I carefully measured out 4.2 ounces of lye into a glass jar and then slowly mixed it into my cold water. I continued to stir until the lye was completely mixed in. It didn't fizz at me at all during this process and I felt quite safe.
The amount of lye you use can be adjusted to the particular soap you are making. If you're adding in other oils to the soap, or mixing fats, or superfatting to your own amount, then you will want to adjust the amount of lye you use. Refer back to the fat to lye ratio table link in step 3 to come up with your own recipe.
I readied my bacon bits and my color at this point because once you combine the lye and the lard things start to happen and there is no going back.
Step 6: Mixing the Soap
With all of your ingredients ready, your gloves and eye protection on and your mixing implements and plastic bowls ready to go, you can begin the mixing process.
I first poured all of the fat into my plastic bowl and then placed the bowl in a warm water bath (105-110 Fahrenheit degree water). The warm water not only moderates the temperature of the soap as it's being formed, but it also speeds up the reaction slightly - I didn't want to be mixing the fat and the lye together for hours on end.
Then, take the water/lye mixture and slowly pour it into the fat while you continue to mix.
Keep mixing for a while. Now depending on your temperatures, the type of fat your using and your lye to fat ratio the mixture should begin to thicken and "trace" (this is when it become sort of a semi-solid like soft peanut butter) in anywhere from 5 to 30 minutes. You need to be mixing this whole time - this is the real challenge of at home soap making in my opinion.
After mixing the liquid soap for 15 minutes by hand I decided to use a power mixer - I used the things they use to make smoothies and vitamin shakes. Within 5 minutes of using the power mixer it began to thicken up nicely and I was able to see some tracing. I would recommend using a power mixer if yours isn't thickening by hand - it really worked well. Stay away from using a blender or hand mixer that has beaters on the end. It will splatter everywhere and will add air bubbles to your soap. The vita-mixer makes less mess and wont add in any air bubbles.
Once the soap began to trace I returned to stirring by hand. I then mixed in about 3/4 of the container of bacon bits. I then poured off about half of my mixture to keep it white and then squeezed about 15 drops of red food coloring into my remaining mixture to turn it red. I didn't do any more power mixing at this point because it would have chopped up my bacon bits.
Step 7: Pouring Into the Molds
You only have about 15 minutes from the moment the soap traces to when it starts to really harden and become difficult to work with. If you're just pouring the soap into molds thats plenty of time, but I wanted to use two different colors and try to make the soap look like actual bacon, so it took some more time. I asked my friend Mike for help.
We first filled each bacon mold about half way with the white soap. Then we went back and filled in the rest with the red. I used a spoon to try and mix the two colors together a bit in an attempt to make it look like strips of bacon meat and fat. This only sort of worked. I'd love suggestions of how to get more accurate marbling of the bacon if anyone has any ideas.
With the bacon molds filled and still plenty of soap left over in the plastic bowl, we poured off some of the white soap mixture and turned it yellow with dye. Mike and I then poured that mixture into the yolk section of the plastic egg molds and then filled in with white on top of that. This actually created a pretty nice fried egg!
When we still had even more soap left over from that I poured it into an ice cube tray to make some travel bars.
Step 8: Curing and Trimming
At this point what you have is really just fat mixed with lye. It takes about 2 weeks for all the fat to saponify and turn into soap. I covered the molds with plastic wrap and left them to dry above the kitchen cabinets so they wouldn't be disturbed. You can remove the soap from the molds after about a day but it still needs to continue curing before you can use it.
During this time the soap hardens, dries and loses a bit of its coloring. The white turned more white and the red turned to pink a little. The ph of the soap will drop from around 11 to around 9 or 8. You can test to see how your soap is doing by testing its ph with litmus paper, or just by giving it a quick smell. I could smell the lye after a few days but after the two weeks the caustic odor was completely gone. This process might take a little shorter or a little longer depending on your exact recipe and the drying conditions.
Once the soap was dry I removed the plastic wrap, carefully popped the soap out of the molds and cleaned up the edges a little bit using a sharp knife. I broke one strip of bacon taking it out of the mold, but everything else released pretty easily.
Step 9: Testing
Once the soap had cured it had to be tested. I called upon my friend Brian for help.
In order to test the soap we first had to get dirty. Having just swept the floor in our whole apartment we had a nice pile of dust and dirt sitting on our floor. Brian got right in there.
We then headed to the bathroom, turned on the water and washed with the soap.
The soap lathered better than I had expected as you can see in the third picture below. Brian reported that it felt nice and there wasn't too strong of an odor as he used it. I was afraid that after washing your hands with the soap that you would need to wash your hands again to get the bacon soap off - but that wasn't the case, he dried his hands and left the bathroom. Whew!
The bacon soap worked!