Rapeseed Oil (high erucic acid)
INCI Brassica Campestris Seed Oil. CAS 8002-13-9, 90989-79-0; EC 232-299-0, 292-737-1, as CosIng gives them. Also: Turnip rape oil, Colza oil, Ravison oil, Sarson oil, Toria oil.
Published values
| Saponification value | 168–181 mg KOH/g |
| Used by the calculator | 174.5 mg KOH/g (midpoint) |
| SAP for NaOH | 0.1244 g/g |
| Iodine value | 94–120 g I₂/100 g |
| INS (SAP − IV) | 68 |
| Melting point | — |
| Unsaponifiable matter | ≤ 2 % |
Soapmaking books print about 0.128 g NaOH per g (median of 4 books). One soapmaking book prints 0.132 g NaOH per g for rapeseed oil, which is right for the low-erucic oil sold for cooking today, the same oil as canola (182-193 mg KOH/g). This record is the old high-erucic rapeseed, whose long erucic acid chains need less lye: the Codex standard gives 168-181, and we use 174.5 (0.124). If your bottle is ordinary rapeseed or canola oil, use the low-erucic record.
A bar made of 100 % Rapeseed Oil
Conventional qualities summed from the fatty-acid groups; a single-oil bar is a reference point, not a recipe.
How much lye
| Oil | NaOH | KOH |
|---|---|---|
| 500 g | 59.1 g(56.9–61.3) | 82.9 g(79.8–86.0) |
| 1 kg | 118.2 g(113.8–122.6) | 165.8 g(159.6–172.0) |
| 1 lb (454 g) | 53.6 g(51.6–55.6) | 75.2 g(72.4–78.0) |
| 2 lb (907 g) | 107.2 g(103.2–111.2) | 150.4 g(144.8–156.0) |
For this oil alone at 5 % superfat, with pure sodium hydroxide (NaOH) or pure potassium hydroxide (KOH); in brackets, across the published range of its saponification value. KOH is usually sold at 90 %: divide by 0.9. For a whole recipe, open the calculator.
Fatty-acid profile
Saturated : unsaturated 8 : 92
| Fatty acid | Published range, % | Used | |
|---|---|---|---|
| Myristic acid | C14:0 · saturated | 0–0.2 | 0.1 |
| Palmitic acid | C16:0 · saturated | 1.5–6 | 3.8 |
| Palmitoleic acid | C16:1 | 0–3 | 1.5 |
| Stearic acid | C18:0 · saturated | 0.5–3.1 | 1.8 |
| Oleic acid | C18:1 | 8–60 | 34.0 |
| Linoleic acid | C18:2 | 11–23 | 17.0 |
| α-Linolenic acid | C18:3 n-3 | 5–13 | 9.0 |
| Arachidic acid | C20:0 · saturated | 0–3 | 1.5 |
| Gadoleic acid | C20:1 | 3–15 | 9.0 |
| Behenic acid | C22:0 · saturated | 0–2 | 1.0 |
| Erucic acid | C22:1 | 2–60 | 31.0 |
| Lignoceric acid | C24:0 · saturated | 0–2 | 1.0 |
Guides that discuss it
- SAP values: what they measure and why tables disagree
- Soap from used cooking oil: how much lye, and how to clean the oil
- The 25er-Rezept: Germany's four-oil beginner soap, with or without palm
Compared with other oils
Where these numbers come from
Verbatim mirror of the FAO file CXS_210e.pdf; the official FAO link was Cloudflare-gated at retrieval. Table 1 (Section 3.1) = mandatory GLC fatty-acid ranges, % of total fatty acids, ND = not detectable (<=0.05%). Table 2 (Appendix 'Other quality and composition factors') gives saponification value, iodine value (Wijs) and unsaponifiable matter of CRUDE oils; the Appendix is explicitly ADVISORY (a product not meeting it may still conform). This print predates the 2021-2025 amendments; the 2024 additions (avocado, camellia seed, sacha inchi, high-oleic soya bean) are not included.
Fatty acids from CXS 210 Table 1 (mandatory GLC ranges, % of total fatty acids; 'ND' = not detectable, <=0.05%, entries that are ND-only are omitted; C17:0, C17:1, C20:2, C22:2 and C24:1 columns omitted because they are outside the acids this database records). The saponification value, the iodine value and the unsaponifiable share from Appendix Table 2 (crude oils; ADVISORY, not mandatory; unsaponifiable converted from g/kg). No 'typical' values are printed in the standard, so none are given. Erucic acid printed '> 2.0-60.0' (i.e. above the 2 % low-erucic limit, up to 60 %). C24:1 ND-3.0, C22:2 ND-2.0, C20:2 ND-1.0 omitted (outside key list).
This record is part of the open ingredient database (ODbL), which you can download as CSV or JSON. Found an error or a better primary source? Corrections with a link to the document are welcome at support@soapformulator.com.