Scent Almanac
Classic cold-process bar
A balanced, creamy everyday bar from olive, coconut, shea, avocado and castor oils, made from scratch with lye and cured for 4–6 weeks.
- Difficulty
- ●●○
- Time
- active 1.5 h · cut in 24–48 h · cure 4–6 weeks
Safety first
- Wear chemical-splash goggles (not just glasses), nitrile or rubber gloves, long sleeves and closed shoes from the moment the lye container opens until the raw soap is put away.
- Mix lye solution in a well-ventilated spot: under a running range hood, by an open window, or outdoors. Don't lean over it. The fumes in the first minute sting the lungs.
- Always add lye to water, never water to lye ('snow falls on the lake'). Pouring water onto lye can erupt and splash boiling caustic liquid.
- Mix and hold lye in a heavy stainless steel or #5 PP plastic container, and stir with stainless or silicone. NEVER use aluminum, which reacts violently and gives off hydrogen gas. Avoid glass, which lye etches and can crack.
- Keep children and pets out of the room until the lye, raw soap and all tools are cleaned up and put away.
- Keep vinegar handy for wiping lye or raw soap off counters and floors. It is for surfaces only. For skin and eyes, use plain running water: flush for 15 minutes. For eyes, flush for 15 minutes and get medical help.
- Weigh everything (oils, water and lye) on a digital scale in grams. Never measure by volume.
- Run every recipe through a lye calculator before you make it, including this one and any time you swap an oil. The preset here opens in the app's lye calculator.
- Store lye sealed, labeled and out of reach. Raw soap stays caustic for a day or two, so wear gloves to unmold and cut it.
Steps
- Run the recipe through the lye calculator and print or write down the exact weights. Put on goggles, gloves and long sleeves, and clear the room of children and pets.
- Weigh the distilled water into a stainless steel or #5 PP container. In a ventilated spot, slowly add the weighed lye to the water (never water to lye) while stirring until it's clear. It will quickly get hot, near 200°F (93°C). Set it somewhere safe to cool.
- Weigh and melt the coconut oil and shea butter, then add the liquid oils (olive, avocado, castor).
- Let the lye solution and oils cool to about 90–110°F (32–43°C), within about 10°F (5°C) of each other.
- Pour the lye solution into the oils down the shaft of the stick blender to avoid splashing. Stick-blend in short bursts, stirring with the blender off in between, until the batter reaches light trace: it looks like thin pudding and a drizzle leaves a faint trail on the surface.
- Stir in the fragrance, and color if using, by hand or with a few short pulses. Some fragrances speed up trace, so work promptly.
- Pour into the mold and tap it down to release air. Spritz the top with 91–99% isopropyl alcohol to help prevent soda ash.
- Gel phase or not: for brighter colors and a slightly translucent look, cover and insulate the mold with a towel to encourage gel. To prevent gel (for milk or honey soaps, or a matte look), leave it uncovered in a cool room or put it in the fridge for 24 hours.
- After 24–48 hours, when the soap is firm and no longer tacky, unmold it and cut it into bars about 1 in (2.5 cm) thick. Wear gloves, because fresh soap is still caustic.
- Cure the bars on a rack with airflow, not touching, out of direct sun, for 4–6 weeks. Turn them once a week.
- Check it's safe before use: touch a bar to the tip of your tongue (the zap test). A 'zap' like a 9-volt battery means excess lye. Or press a wetted pH strip against it: 9–10 is normal for soap, and above 10 means it needs more cure or has a problem.
- Clean tools with gloves on. Let the raw soap on them saponify for a day, then wash with hot soapy water.
NaOH138.0 g · 4.9 oz
Water (distilled)280 g · 9.9 oz
2.0 : 1 water to lye
Fragrance50 g · 1.8 oz
Batch weight1468 g · 51.8 oz
| Oil | % | Weight |
|---|---|---|
| Olive oil | 40.0 | 400 g · 14.1 oz |
| Coconut oil (76°) | 25.0 | 250 g · 8.8 oz |
| Shea butter | 15.0 | 150 g · 5.3 oz |
| Avocado oil | 15.0 | 150 g · 5.3 oz |
| Castor oil | 5.0 | 50 g · 1.8 oz |
Bar qualities
Hardness
37
Cleansing
17
Conditioning
59
Bubbly
21
Creamy
24
Iodine
63
INS
141
Green bands are the usual ranges for a balanced bar. Liquid soap, castile and salt bars fall outside them on purpose.
Lye safety: wear goggles and gloves. Add lye to water, never water to lye, in a heat-safe stainless or #5 plastic container, with good ventilation and no children or pets nearby. Always double-check a lye amount with a second calculator before you make soap.
If something goes wrong
- Seizing (batter turns solid in the pot)
- Usually a fragrance that accelerates (florals, spice, vanilla notes) or oils and lye that are too warm. Glop it into the mold fast and bang it down, or rescue it by hot-processing in a crockpot. Next time, soap cooler, add a tricky fragrance at emulsion (not trace), and stir it in by hand.
- Ricing (small hard grains form when fragrance goes in)
- The fragrance reacted with the hard oils. Keep stick-blending: the grains often smooth out. If not, hot-process the batch. Test that fragrance in a small batch first next time.
- Soda ash (white powdery film on top)
- Harmless: unreacted lye met air before saponification finished. Steam it off, plane it off, or wash the bar once. Prevent it by spritzing the fresh top with 91–99% isopropyl alcohol, covering the mold, and using a higher lye concentration.
- Glycerin rivers (translucent streaks in colored bars)
- Cosmetic. They come from partial gel with titanium dioxide and a lot of water. Use a higher lye concentration (less water), mix titanium dioxide in oil rather than water, and either fully gel or fully prevent gel.
- Liquid or crusty white pockets inside the bar, or a strong zap
- Possible lye pockets or a measuring error. Don't use it. Recheck your recipe in a lye calculator and your scale. If you can't confirm the error, discard it as hazardous (wear gloves), or grate and rebatch only if the numbers show it's just a mixing issue.
- Orange spots (DOS) appear during cure
- Rancid oils. Use fresh oils, keep high-linoleic oils low, add rosemary extract to the oils, cure with airflow out of sun, and don't wrap bars airtight while they cure.