Castile Soap (100% Olive Oil) Recipe
Traditional castile soap made from 100% olive oil. A very gentle bar that needs a long cure.
BeginnerCold process5% superfatCure: 6 months
Why this recipe works
Pure olive oil soap is one of the mildest bars you can make. It is slow to trace and soft at first, but after a long cure it becomes a very hard, long-lasting bar.
Ingredients
| Ingredient | % | Grams | Ounces |
|---|---|---|---|
| Olive Oil | 100% | 1000 g | 32 oz |
| Sodium hydroxide (NaOH) | 128.3 g | 4.1 oz | |
| Distilled water | 256.5 g | 8.2 oz |
Amounts are for 1000 g (or 32 oz) of oils, a batch of about 1385 g before curing. Water is 2:1 to lye by weight.
Method
- Put on gloves and eye protection and clear the work area.
- Weigh the water (or frozen liquid) into a heat-safe jug. Weigh the lye separately, then slowly add the lye to the water, never the other way round. Stir until dissolved and leave to cool.
- Weigh and melt the hard oils and butters, then add the liquid oils.
- When the oils and lye solution are both around 35–45°C (unless the tips say otherwise), pour the lye solution into the oils.
- Stick blend in short bursts until light trace (like thin custard). Stir in fragrance, colour and any additives.
- Pour into the mould, cover and leave for 24–48 hours.
- Unmould, cut into bars and cure on a rack in a dry, airy place.
Tips
- Expect a long time to trace. A stick blender is essential.
- Leave it in the mould for 3–5 days; it stays soft for longer than most recipes.
- Cure for at least 6 months. The lather is low and slightly slippery; that is normal for castile.
⚠️ Lye safety
Lye is caustic. Wear gloves and eye protection, work in a ventilated room, keep children and pets away, and always add lye to water. Always run any recipe through a lye calculator before making it, especially if you change an oil.
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