Macadamia nut oil in soap making
Published by The Soap Brain Team
Macadamia nut oil is a balanced soap-making oil rich in oleic acid (55%). A gram of it turns to soap with about 0.139 g of NaOH (lye). It can lean cleansing, conditioning or hardening — a lot depends on what you blend it with. Most soapers use it at 5–15% of their oils.
Fatty-acid profile
Macadamia nut oil is a balanced oil, carrying a mix of saturated and unsaturated fatty acids, so it can play several roles in a recipe depending on what it is blended with.
Macadamia nut oil is about 13% saturated fat and 57% 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 | 55% | a monounsaturated fatty acid that makes a gentle, conditioning, moisturising bar with a slick, lower lather and a slower trace |
| Palmitic acid | 9% | a saturated fatty acid that builds a hard, long-lasting bar with a stable, creamy lather |
| Stearic acid | 4% | a saturated fatty acid that adds hardness and a thick, stable lather; a large share can speed up trace |
| Linoleic acid | 2% | a polyunsaturated fatty acid that is very conditioning but oxidises readily — a driver of DOS (dreaded orange spots) at high levels |
Macadamia nut oil in the bar
Macadamia nut 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.
Macadamia nut oil traces at a fairly typical pace; how fast the whole batch moves will depend mostly on the other oils, your temperatures and any fragrance you add.
Macadamia nut oil is versatile in a blend — it can lean cleansing, conditioning or hardening depending on what you pair it with, so treat it as a flexible middle-of-the-recipe oil.
Closest substitutes for Macadamia nut oil
Out of Macadamia nut 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) |
|---|---|---|---|---|
| Macadamia nut oil (this oil) | 13 | 0 | 57 | 0.139 |
| Emu oil | 30 | 0 | 60 | 0.138 |
| Baobab oil (refined) | 24 | 0 | 70 | 0.135 |
| Cottonseed oil | 26 | 1 | 69 | 0.137 |
| Peanut oil | 13 | 0 | 76 | 0.135 |
Using Macadamia nut oil in a recipe
One gram of Macadamia nut oil needs about 0.139 g of NaOH (sodium hydroxide) to turn fully to soap, within a documented range of 0.135–0.143 g/g across sources. The calculator below uses this value; always confirm the lye weight before you mix.
Its iodine value is about 73 — 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 Macadamia nut oil at roughly 5–15% of their oils.
Maker's note: Skin-mimicking conditioning oil, thanks to its ~20% palmitoleic acid (which our numbers don't score).
Calculate lye for Macadamia nut oil
The calculator below is pre-loaded with Macadamia nut 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
- Artiz Soap — SAP Value Table — SAP cross-check
- PubMed — nut oil fatty-acid study (walnut/almond/peanut/hazelnut/macadamia) — fatty-acid profile
SAP data last updated · 51 oils covered.
Macadamia nut oil soap FAQ
- Can you make soap with 100% Macadamia nut oil?
- It is not recommended. Macadamia nut 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 Macadamia nut oil?
- A 5% superfat is a safe, common starting point for recipes using Macadamia nut 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 Macadamia nut oil speed up or slow down trace?
- Macadamia nut oil traces at a fairly typical pace; how fast the whole batch moves will depend mostly on the other oils, your temperatures and any fragrance you add.