Marula oil in soap making
Published by The Soap Brain Team
Marula oil is a conditioning soap-making oil rich in oleic acid (70%). A gram of it turns to soap with about 0.139 g of NaOH (lye). It makes a mild, gentle bar and pairs well with a harder, cleansing oil. Most soapers use it at 5–15% of their oils.
Fatty-acid profile
Marula oil is a gentle, conditioning oil, mostly unsaturated fatty acids that leave a mild, moisturising bar with a softer, lower lather. It pairs naturally with a harder, more cleansing oil to firm the bar up and add bubbles.
Marula oil is about 22% saturated fat and 76% unsaturated — that unsaturated majority is what makes it conditioning and slower to trace, but softer on its own.
| Fatty acid | Share | What it does in soap |
|---|---|---|
| Oleic acid | 70% | a monounsaturated fatty acid that makes a gentle, conditioning, moisturising bar with a slick, lower lather and a slower trace |
| Palmitic acid | 14% | a saturated fatty acid that builds a hard, long-lasting bar with a stable, creamy lather |
| Stearic acid | 8% | a saturated fatty acid that adds hardness and a thick, stable lather; a large share can speed up trace |
| Linoleic acid | 6% | a polyunsaturated fatty acid that is very conditioning but oxidises readily — a driver of DOS (dreaded orange spots) at high levels |
Marula oil in the bar
Marula oil gives a mild, low, slick lather on its own. Blended with a bubbly, cleansing oil it contributes body and mildness while the partner oil supplies the bubbles.
High-oleic Marula oil traces slowly, which gives you comfortable working time for swirls and layers. In exchange the bar is soft at first and rewards a longer cure — four to eight weeks — to harden fully and last in the shower.
In a blend Marula oil is the conditioning, skin-feel component and can often make up the bulk of the oils. Add a firmer, more cleansing oil — coconut, palm or a hard butter — to bring hardness and bubbles the finished bar would otherwise miss.
Closest substitutes for Marula oil
Out of Marula oil? These oils behave most like it in a bar — ranked by how close their hardness, cleansing and conditioning profile and lye (SAP) requirement are. The numbers are predicted properties for a 100% single-oil bar, not a safety guide; always recalculate the lye when you swap an oil.
| Oil | Hardness | Cleansing | Conditioning | SAP (NaOH) |
|---|---|---|---|---|
| Marula oil (this oil) | 22 | 0 | 76 | 0.139 |
| Rice bran oil | 23 | 0 | 75 | 0.133 |
| Baobab oil (refined) | 24 | 0 | 70 | 0.135 |
| Wheat germ oil | 18 | 0 | 80 | 0.133 |
| Cottonseed oil | 26 | 1 | 69 | 0.137 |
Using Marula oil in a recipe
One gram of Marula oil needs about 0.139 g of NaOH (sodium hydroxide) to turn fully to soap, within a documented range of 0.134–0.143 g/g across sources. The calculator below uses this value; always confirm the lye weight before you mix.
Its iodine value is about 74 — a moderate value, a good all-round balance of hardness and conditioning. Iodine value is only a rough guide, not a hard rule, but it gives you a feel for how a bar built around this oil will wear.
Most soapers use Marula oil at roughly 5–15% of their oils.
Maker's note: Olive-like, high-oleic conditioning oil with good oxidative stability.
Calculate lye for Marula oil
The calculator below is pre-loaded with Marula oil. Enter your weights, add other oils, and it works out the exact NaOH (lye) weight, water and quality numbers. Always weigh lye, oils and water — never measure by volume, wear gloves and eye protection, and add lye to water (never the reverse).
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Where these numbers come from
Every figure on this page is backed by at least two independent references, listed below — so you can check our work instead of taking our word for it.
- From Nature With Love — Saponification Chart — SAP range
- Wikipedia — Marula oil — SAP ~188–199 (academic ref)
- Afrinatural — Marula Seed Oil Profile — fatty-acid profile
SAP data last updated · 51 oils covered.
Marula oil soap FAQ
- Can you make soap with 100% Marula oil?
- It is not recommended. Marula oil shows its best in a blend, usually up to about 15% of the oils. On its own the bar would be unbalanced — too soft or low-lathering for everyday use.
- What superfat should I use with Marula oil?
- A 5% superfat is a safe, common starting point for recipes using Marula oil; adjust to taste once you know how the finished bar feels. Never drop to 0% or below without a deliberate reason — the calculator will ask you to confirm it.
- Does Marula oil speed up or slow down trace?
- High-oleic Marula oil traces slowly, which gives you comfortable working time for swirls and layers. In exchange the bar is soft at first and rewards a longer cure — four to eight weeks — to harden fully and last in the shower.