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Household bars

Kitchen bar

Two bright white kitchen soap bars on a slatted wooden soap dish beside a wooden dish brush and a small dish of coconut oil on a deep green backdrop

A hard, unscented kitchen bar for dishes, pans and worktops: 70 % coconut oil to cut grease, a little olive oil to soften the edge and castor oil for a quick lather. Rub a wet brush over it and wash up as usual.

Skill
Beginner
Method
Cold process
Batch
1000 g of oils about 1470 g of batter
Hands-on
45 min
Cure
4 weeks
Gel phase
Either way gel or not, both work
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What you need

For 1000 g of oils, which fills a 1.5 litre loaf mould. Weigh everything, liquids included.

Coconut Oil · 70.0 % 700 g 24.69 oz
Olive Oil · 20.0 % 200 g 7.05 oz
Castor Oil · 10.0 % 100 g 3.53 oz
Sodium hydroxide (NaOH) · the lye, 100 % pure 164.5 g 5.80 oz
Distilled water · for a 35 % lye solution 305.5 g 10.78 oz
Superfat
2 %
Temperatures
Oils and lye solution at 32 to 38 °C (90 to 100 °F), left uncovered

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Method

  1. Get ready

    Put on goggles, gloves and long sleeves, open a window and set out a 1.5 litre loaf mould where it can stay for a day. Keep children and pets out of the room.

  2. Weigh everything

    Weigh 700 g coconut oil into the pot, 200 g olive oil and 100 g castor oil into a jug, 305.5 g distilled water into a heat-safe lye jug and 164.5 g sodium hydroxide into a small, dry container.

  3. Make the lye solution

    Pour the sodium hydroxide slowly into the water, never the water onto the lye, and stir until it runs clear, keeping your face away from the vapour. Leave it to cool to 32 to 38 °C (90 to 100 °F), labelled and out of reach.

  4. Melt the coconut oil

    Warm the coconut oil until it is just clear, then pour in the olive and castor oils. Let the oils settle at 32 to 38 °C (90 to 100 °F); much below about 24 °C (75 °F) the coconut oil starts to set again.

  5. Blend to light trace

    Pour the lye solution into the oils down the shaft of the stick blender and blend in short pulses, stirring between them. This much coconut oil traces fast, so stop at light trace, when a drizzle leaves a faint line on the surface.

  6. Pour and leave it uncovered

    Pour into the mould and tap it on the worktop to let air bubbles rise. Leave it uncovered in a cool room with no towel over it: a batch this high in coconut oil makes plenty of heat of its own and can crack if it is kept warm.

  7. Clean up with your gloves on

    Wipe the raw batter off the pot and tools with paper towels into the bin, then wash everything in hot soapy water.

  8. Cut it the same day

    Coconut soap sets hard quickly. With gloves on, unmould and cut it as soon as it holds a clean edge, often 4 to 12 hours after pouring; left too long, it cuts with chips and cracks.

  9. Label the bars

    Label the bars as kitchen soap and keep them apart from your bathroom soap, so no one mistakes them for hand soap.

  10. Cure for four to six weeks

    Stand the bars on a rack with air around them for four to six weeks. The drier the bar, the longer it lasts at the sink.

  11. Wash up with it

    Rub a wet brush or cloth over the bar, then wash dishes, pans and worktops as usual and rinse them in clean water. For a greasy pan, work the bar straight onto the brush.

  12. Keep it on a draining dish

    Stand the bar on a slatted or draining soap dish between uses, never in a puddle: a bar that sits in water goes soft and wastes away.

Tips

  • This is a cleaning bar, not a hand soap. So much coconut oil at a 2 % superfat makes a very cleansing soap, and across the oils' published saponification ranges it could even carry a trace of free lye, so if your skin is sensitive, wear gloves for the washing up.
  • Our solid dish and kitchen bar goes further in the same direction, with 80 % coconut oil and cocoa butter for a harder bar that lasts longer at a wet sink. For a gentler bar at the sink that also washes hands, our citrus kitchen bar is made at an everyday 5 % superfat.
  • The castor oil makes the batter thicken a little faster than coconut oil alone, so have the mould ready before you start blending.

Why make it

A bar for pans, dishes and worktops. Seventy per cent coconut oil makes it strongly cleansing, 48 on our scale against the 12 to 22 of a skin soap, and coconut soap stays dissolved where others separate out: the soap trade relied on it for marine soap that lathers in sea water (Simmons and Appleton, 1908). Castor oil brings the lather up quickly on a wet brush, and the 2 % superfat leaves little oil behind on the plates. Many makers like a solid bar at the sink because it replaces a bottle of washing-up liquid. It cleans the way any soap does, lifting grease into the rinse water, and we claim nothing more for it. It is not a hand soap either: if washing up leaves your hands sore, the NHS advises protecting them with gloves.

Sources

What tradition, makers' experience and research say about soaps like this, each labelled for what it is. It is not medical advice, and no soap treats a skin condition: if you have one, ask a doctor or pharmacist.

What the numbers say

  • Lauric acid 34.4 %
  • Myristic acid 13.2 %
  • Palmitic acid 9.1 %
  • Stearic acid 2.9 %
  • Ricinoleic acid 8.9 %
  • Oleic acid 19.5 %
  • Linoleic acid 4.1 %
  • Other 10.7 %

Saturated : unsaturated 68 : 32

Hardness 60 above 29–54
Cleansing 48 above 12–22
Conditioning 33 below 44–69
Bubbly lather 56 above 14–46
Creamy lather 21 16–48

Computed from the fatty acids of the fats above. The bands are what the craft has settled on, not chemistry — a bar outside one is not wrong.

Try it differently

8 variations

The same soap with one thing moved. Each opens in the calculator ready to change again.

From the guides

All guides
Beginner 9 min read

Laundry soap bars and household soap

Why laundry and kitchen bars are high in coconut and made with almost no superfat, how to grate one into laundry powder, and what washing soda and borax do.
Advanced 10 min read

Soap in hard water: scum, chelators and rinse

Why soap turns to scum in hard water, how much soap each litre wastes, what a chelator in the bar can and cannot do, and why coconut soap copes best.
Intermediate 11 min read

Superfat and lye discount: why recipes leave some oil unsaponified

What superfat and lye discount mean, how the calculator applies them, where makers set them for each soap, and why oil added at trace isn't the oil left over.

Where these proportions come from

Our own formulation: 70 % coconut oil, the most cleansing soap there is and the one that copes best with hard water, 20 % olive oil to soften its edge a little, and 10 % castor oil for a quick lather on a wet brush, at a 2 % superfat so that it rinses clean and leaves little oil on the dishes.

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