mix lye solution
- weigh sodium hydroxide
- add sodium hydroxide to water
Important - read the safety instructions for handling sodium hydroxide (also known as caustic soda, lye or NaOH) before mixing.
When measuring the ingredients into the jugs be sure to remember to tare or zero the scales. Taking accurate weight measurements is a safety issue and its importance cannot be overstated.
1. Weigh the water into the first jug.
2. Weigh the sodium hydroxide into the second jug and set aside.
3. Carefully pour the sodium hydroxide into the water (not the water to the sodium hydroxide) in a well ventilated area and stir gently until completely dissolved. Cover and set aside to cool (this may take several hours).
measure
Accurately weigh the oils, place in the stainless steel pot (don't ever use aluminium as it will react with the lye) and heat slowly to 40°C. Remove from heat.
mix
- add lye solution
Carefully pour the lye solution into the soapmaking oil in a steady stream and stir gently. The mixture will thicken and become opaque.
- stick blender makes stirring easy!
stir
Keep stirring until you can drizzle some of the mixture from the spoon back onto the surface leaving a pattern. This is known as "tracing" and it looks a bit like a thick custard or pudding mix.
Recipes higher in saturated fat (coconut,palm etc.) will reach tracing more quickly than those containing unsaturated oils such as olive oil (see notes).
A hand held blender, or "stick" blender, can shorten tracing time considerably. For instructions, see notes.
- heavy trace
trace
Once tracing occurs keep mixing till the soap has reached the consistency of thick (but not stiff) custard, and then add any additives (nutrient oils, colouring, vegetable solids, etc.) and stir thoroughly to combine.
- add essential oil
add essential oil
Add any essential oils and only stir just enough to combine the essential oil with the soap mixture. Over stirring at this stage may cause seizing.
soapmaking equipment
The following equipment list is the minimum you will need.
Note: All measurements are given in metric, including temperatures.
- Accurate kitchen scales
- Two kitchen thermometers (should be capable of measuring temperature range of 25°C up to 200°C)
- One 8-12 litre stainless steel pot
- Two 2 litre dishwasher proof plastic jugs with tight fitting lids
- Two long handled plastic spoons
- Two plastic spatulas
- Stainless steel or plastic ladle
- Hand held blender (optional)
- Polystyrene box (for insulating soap mixture)
- Soapmaking moulds. (see notes)
safety equipment
- Safety goggles
- Rubber gloves
- Full length apron