Lavender & Tea Tree Soap/Shampoo
A few years ago I was inspired to start making my own soaps using garden produce after seeing a video by CollieryGarden which seemed to show quite a simple process. I made some calendula soap (which I am still using!). I found it actually works really well as a solid shampoo bar and have been using it for that too! This is a natural soap based recipe that mixes lye (Sodium hydroxide) with fats to cause the soap (saponification) reaction.
In this batch I have used home grown dried lavender and tea tree oil.
A quick word of warning that sodium hydroxide is very corrosive so it is important to use protection – certainly goggles or large glasses to cover your eyes and avoid contact with skin. When the solid hydrogen perioxide is added to the water the reaction is exothermic and gives out heat. It does actually get quite hot (70 degrees Celcius ish). Do this in a well ventilated area i.e outside or right next to an open door at least. The fumes are very irritant so you do not want to breathe these in.
The basic idea of making natural soaps is to mix the liquid sodium hydroxide and liquid fats when they are within 10 degrees celcius of each other and then to blend together to allow the saponification reaction to occur. You can tell the reaction has occured because it goes quite like custard in texture. It is important to measure all the ingredients to the gram and to keep to the amounts of each fat used. This is because each different type of fat needs a specific amount of sodium hydroxide solution for the reaction to occur fully. If you change the fat proportions or types the amount of sodium hydroxide required would need to be recalculated.
Many thanks to CollieryGarden for the inspiration and recipe! Take a look – lots of great videos!
Recipe:
*280ml water (cold)
*120g NaOH (Lye/Caustic Soda).
*450g lard
*50g shea butter
*200g coconut oil
*160g olive oil
*Tea tree oil (approx 2 tsp)
*Dried lavender (3 tbs)
measure sodium hydroxide 
measure cold water 
add hydrogen peroxide to water and stir to dissolve 
Measure fats 
Heat in bain maire until blended 
Check temp of hydrogen peroxide 
Check temp of fats 
When within 10 degrees blend with a stick blender 
When custard appearance is reached add in oil and lavender 
Mix well. Add to a soap mould and allow to set for 2-3 days.
After 2-3 days you can turn the soap out of the mould and slice into individual bars. I then place on a tray and leave to cure further for about 4-6 weeks and it is ready to use.