I'm going to include a recipe for a soap that can be made from what you can gather in nature seeing as how there is a difference between making soap at home and soap made in a SHTF situation. This recipe doesn't have ingredients that needs domesticated or exotic fats or sodium hydroxide (store bought Lye). It uses deer tallow and Potassium hydroxide (wood ash lye). Wood ash will give you a softer soap but if you have a bit of salt to spare you can add some in the mixing to render a hardness you desire. In a SHTF situation, the use of salt for soap is a vanity over its other better uses though.
If you don't know how to make wood ash lye or render tallow you can either find the information yourself or ask me for a pdf files explaining the process.
Here is the recipe below. It is 5% superfatted and all measurements are in pounds then again in ounces then again in grams so you have more of a chance of finding a scale system to weigh your 3 ingredients. ***Note that the lye weight is dry weight. You have to boil down your lye to a dry state so that it takes out the guess work of liquid home made lye. Also, this soap can go rancid after a year or so if not kept airtight and dark after the drying procedure.
If you like this wood ash recipe I also have it for beef, chicken, pig, sheep, goat, goose and milk fat.
Wood Ash Lye (potassium hydroxide)= 0.733 pounds or 11.73 ounces or 332.66 grams
Water(softer the better)= 1.52 pounds or 24.32 ounces or 689.5 grams
Deer tallow= 4 pounds or 64 ounces or 1814.4 grams
Procedure: 1. add the lye to the water. (it will get hot) let it cool until it is just offensive to touch (about 115-125 degrees F)
2. Bring tallow up to same temperature.
3. use crank hand mixer, electric stick blender or whisk to stir at temperature until trace.
4. After trace, keep mixing while letting cool slowly until it thickens well.
5. If salt is added, pour into molds, if left as soft soap you can put it in a tub to be scooped.
6. it has cured the water out when it has lost about 38% of its weight in drying
Hope this helps keep people healthy in a SHTF situation