Charcoal and Beer soap
Prep time: 
Total time: 
Serves: 12 bars
Oils & butters
  • 40% Olive Oil (400g)
  • 30% Coconut Oil (300g)
  • 10% Sweet Almond Oil (100g)
  • 10% Cocoa Butter (defragranced is best) (100g)
  • 10% Shea Butter (100g)
Liquid & lye
  • 380g beer and water total
  • 140g sodium hydroxide (lye)
  • 1tsp charcoal (about 9 capsules)
  • 10ml black pepper essential oil
  • 10ml bergamot essential oil
The day before
  1. Bring the contents of a 330ml bottle of lager to the boil. Simmer until it stops foaming and then another bit.
  2. Leave to cool in fridge overnight.
Mix the liquid and lye
  1. Cover your work surface and put on gloves and goggles to protect your skin.
  2. Measure your beer by weight and top up to 380g with cold water
  3. In a plastic or stainless steel jug (never aluminium) take it outside and stir in the lye very gradually.
  4. Leave it dissolve completely, during which time it will give off quite a lot of heat and some fumes.
Combine your oils
  1. While the lye is cooling melt the hard oils (coconut, cocoa, shea) in a double boiler until just melted.
  2. In a plastic or stainless steel bowl add the melted oils to the olive and sweet almond oils and stir together.
  3. In another container mix the charcoal powder with a little oil, just about a teaspoon or less to blend.
  4. Combine the essential oils and have them ready to pour.
Combine the oils and lye
  1. Check the outside of the oil bowl and the outside of the lye jug with your hands (in gloves!) and they should both be a little warmer than body heat by now and hopefully around the same temperature.
  2. Pour the lye carefully into the oil mix. Using the back of a spoon or spatula to pour it onto should help avoid splashes.
  3. Mix with a stick blender, then pulse a few times to mix.
  4. It doesn't take long to achieve 'trace', the point of no return where liquid and oil are emulsified, so pulse in small bursts rather than going hell for leather.
  5. At a light trace (think coating sauce in cooking) the mix will be fully bonded and the stick will leave a barely visible trail.
  6. Pour about ⅓ of the mix into a separate bowl or jug and add the charcoal mix to this. Mix with a whisk or pulse barely if needed.
  7. Add the essential oil into each soap mix and whisk with a balloon whisk to blend.
Pour into mould
  1. Pour all the light coloured batter into a prepared mould.
  2. Pour a stripe of the dark batter down the centre of the mould, it will sink to the bottom. Use about half the dark batter.
  3. Using a spatula to break the pour speed, pour the dark batter down each side of the mould. It will sit on top of the light batter.
  4. Insert a chopstick into the soap, the full depth, and quickly draw figures of 8 from side to side to form a swirl.
  5. Tap the mould sharply a few times on a hard surface and knock the air bubbles out.
  1. If you like, cover the mould with cardboard, wrap in a towel or blanket and leave overnight. This optional step will help encourage a gel phase which makes the charcoal darker.
  2. Leave the soap set for 24 - 48 hours before unmoulding and cutting.
  3. Leave for 4 - 6 weeks in a well ventilated place to cure fully before use.
To switch this to a coffee soap, add about 2 tablespoons of used ground coffee, well drained (about a used barista double shot of coffee grounds) instead of the charcoal, and just use water instead of beer. Any other changes should be run through a lye calculator like soap calc (
Recipe by The Zero Way at