Cottonseed oil: SAP value and fatty acids
Cottonseed oil has a saponification value of 193.5 mg KOH/g. One gram needs 0.138 g of sodium hydroxide (NaOH) for bar soap or 0.194 g of potassium hydroxide (KOH) for liquid soap to turn fully into soap, before any superfat.
Key numbers
- SAP, NaOH
- 0.137943 g per g oil
- SAP, KOH
- 0.1935 g per g oil
- Saponification value
- 193.5 mg KOH/g
- Iodine value
- 111.5
- INS
- 82
- INCI name
- Gossypium Herbaceum Seed Oil
Example: 100 g of Cottonseed oil with no superfat needs 13.8 g of 100% NaOH, or 19.4 g of 100% KOH. A 5% superfat uses 5% less.
In soap
Its main fatty acids in our cited profile are linoleic (52.5%) and palmitic (23.9%). The eight fatty acids used in soap-quality scores make up 98.4% of the profile.
On its own it scores 28 for hardness, 1 for cleansing and 71 for conditioning, with a saturated : unsaturated split of 28 : 71.
Fatty-acid profile
| Fatty acid | % of fatty acids | Counts toward |
|---|---|---|
| lauric | 0.1% | hardness, cleansing, bubbly lather |
| myristic | 0.8% | hardness, cleansing, bubbly lather |
| palmitic | 23.9% | hardness, creamy lather |
| stearic | 2.7% | hardness, creamy lather |
| ricinoleic | 0% | conditioning, bubbly and creamy lather |
| oleic | 18.2% | conditioning |
| linoleic | 52.5% | conditioning |
| linolenic | 0.2% | conditioning |
Basis: Codex CXS 210 Table 1 range midpoints (raw; midpoints total 100.0%).
Soap-quality scores (this oil alone)
| Hardness | 28 |
|---|---|
| Cleansing | 1 |
| Conditioning | 71 |
| Bubbly lather | 1 |
| Creamy lather | 27 |
| Iodine | 112 |
| INS | 82 |
Each score adds up certain fatty acids, the way Soap Ledger scores a whole recipe. They are for comparing recipes; they don't predict how a bar will feel, and they say nothing about safety or skin.
Sources
SAP value: 193.5 mg KOH/g (Midpoint of Codex CXS 210 range), from Codex Alimentarius CXS 210-1999, Standard for Named Vegetable Oils (Table 2: chemical and physical characteristics), FAO/WHO Codex Alimentarius Commission. Printed value: 189-198 mg KOH/g.
Published values we checked:
- 189-198 mg KOH/g — FAO/WHO Codex Alimentarius Commission
- 192 mg KOH/g — From Nature With Love (soap/cosmetic supplier)
- NaOH 0.1387 / KOH 0.1954 g alkali per g oil — Certified Lye
Fatty acids and iodine: Codex Alimentarius CXS 210-1999, Standard for Named Vegetable Oils (Table 2: chemical and physical characteristics), FAO/WHO Codex Alimentarius Commission. Also checked: U.S. Department of Agriculture, Agricultural Research Service (Fatty acid nutrients (g/100 g food)).
NaOH and KOH values are converted from mg KOH/g with the molar masses 39.997 and 56.106 and rounded to 6 decimals, exactly as in the Soap Ledger app. Real oils vary by origin, grade and lot: check your supplier's certificate of analysis. Verify every weight before you make this, and follow lye safety. Not a safety or compliance certification.
Last updated .