Tucuma butter in soap making
Published by The Soap Brain Team
Tucuma butter is a cleansing soap-making oil rich in lauric acid (45%). A gram of it turns to soap with about 0.17 g of NaOH (lye). It gives a hard bar with a big, quick lather and is usually kept to a minority of the recipe. Most soapers use it at 3–15% of their oils.
Fatty-acid profile
Tucuma butter is a strongly cleansing oil: its high lauric and myristic content produces a hard bar with a big, quick-rinsing lather. Most makers keep it a minority of the recipe (often under 30%) so the bar cleans well without stripping the skin.
Tucuma butter is about 82% saturated fat and 16% unsaturated — that saturated majority is what lets it firm up a bar and hold a stable lather.
| Fatty acid | Share | What it does in soap |
|---|---|---|
| Lauric acid | 45% | a saturated fatty acid that gives a big, fluffy, fast-cleansing lather; drying to skin above roughly 30% of a recipe |
| Myristic acid | 28% | a hard, cleansing, bubbly saturated fatty acid that usually travels alongside lauric acid |
| Oleic acid | 14% | a monounsaturated fatty acid that makes a gentle, conditioning, moisturising bar with a slick, lower lather and a slower trace |
| Palmitic acid | 6% | a saturated fatty acid that builds a hard, long-lasting bar with a stable, creamy lather |
| Stearic acid | 2.5% | 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 |
Tucuma butter in the bar
On its own Tucuma butter throws a big, quick, bubbly lather — the kind of foam most people associate with a cleansing bar. Balance it with conditioning oils so the lather stays generous without drying the skin.
Tucuma butter traces at a moderate pace and firms up reliably thanks to its saturated fatty acids, making it forgiving for most cold-process work.
In a blend Tucuma butter is the cleansing, lather-making component. It is usually kept to a minority of the oils and paired with conditioning oils like olive or a soft butter, which offset its tendency to dry the skin at higher amounts.
Closest substitutes for Tucuma butter
Out of Tucuma butter? 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) |
|---|---|---|---|---|
| Tucuma butter (this oil) | 82 | 73 | 16 | 0.17 |
| Murumuru butter | 81 | 73 | 14 | 0.175 |
| Palm kernel oil | 73 | 63 | 18 | 0.178 |
| Babassu oil | 74 | 62 | 15 | 0.178 |
| Coconut oil, 76°F | 78 | 66 | 10 | 0.183 |
Using Tucuma butter in a recipe
One gram of Tucuma butter needs about 0.17 g of NaOH (sodium hydroxide) to turn fully to soap, within a documented range of 0.16–0.178 g/g across sources. The calculator below uses this value; always confirm the lye weight before you mix.
Its iodine value is about 16 — a low value, pointing to a hard, long-lasting bar with good shelf life. 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 Tucuma butter at roughly 3–15% of their oils.
Maker's note: Amazonian palm-seed butter with a coconut-family profile; makes a nice foamy lather and a hard bar.
Calculate lye for Tucuma butter
The calculator below is pre-loaded with Tucuma butter. 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.
- SoapGoods — Tucuma Butter, Refined (spec) — usage: cold process up to 15% (the spec table lists SAP as n/a, so SAP here rests on Formula Botanica + the Madar COA below)
- Formula Botanica — 5 Amazonian Butters — SAP 230–250 mg KOH/g, iodine 10–30
- Cosmacon — Tucuma butter (INCI Astrocaryum Vulgare Seed Butter) — fatty-acid profile: lauric 45, myristic 28, oleic 14, palmitic 6, stearic 2,5, linoleic 2, capric <1,5, palmitoleic <1
- Madar Corp / BiOrigins — Tucuma Virgin Butter, Certificate of Analysis (lot 4589002) — SAP 230–250 mg KOH/g (measured 246,8), iodine 10–30; fatty-acid spec — but its printed stearic 10–15 is refuted by its own saturation total
- Crafter's Choice — Tucuma Butter — usage: cold process soap 3–6%
SAP data last updated · 51 oils covered.
Tucuma butter soap FAQ
- Can you make soap with 100% Tucuma butter?
- It is not recommended. Tucuma butter shows its best in a blend, usually up to about 15% of the oils. On its own the bar would be unbalanced — too harsh and drying for everyday use.
- What superfat should I use with Tucuma butter?
- A 5% superfat is a safe starting point. Because Tucuma butter is strongly cleansing, many makers superfat a little higher (around 6–8%) to soften its effect on the skin.
- Does Tucuma butter speed up or slow down trace?
- Tucuma butter traces at a moderate pace and firms up reliably thanks to its saturated fatty acids, making it forgiving for most cold-process work.