Soybean oil, partially hydrogenated (27.5%): SAP value and fatty acids
Soybean oil, partially hydrogenated (27.5%) has a saponification value of 191.45 mg KOH/g. One gram needs 0.136 g of sodium hydroxide (NaOH) for bar soap or 0.191 g of potassium hydroxide (KOH) for liquid soap to turn fully into soap, before any superfat.
Key numbers
- SAP, NaOH
- 0.136481 g per g oil
- SAP, KOH
- 0.19145 g per g oil
- Saponification value
- 191.45 mg KOH/g
- INCI name
- Hydrogenated Soybean Oil
Example: 100 g of Soybean oil, partially hydrogenated (27.5%) with no superfat needs 13.6 g of 100% NaOH, or 19.1 g of 100% KOH. A 5% superfat uses 5% less.
In soap
Its main fatty acids in our cited profile are oleic (44.5%) and linoleic (36.5%). The eight fatty acids used in soap-quality scores make up 99.3% of the profile.
On its own it scores 16 for hardness, 0 for cleansing and 84 for conditioning, with a saturated : unsaturated split of 16 : 84.
Partly hydrogenated soybean oil is firmer than plain soybean oil but needs almost the same amount of lye. Only one supplier table lists it directly.
Fatty-acid profile
| Fatty acid | % of fatty acids | Counts toward |
|---|---|---|
| lauric | 0% | hardness, cleansing, bubbly lather |
| myristic | 0.1% | hardness, cleansing, bubbly lather |
| palmitic | 10.3% | hardness, creamy lather |
| stearic | 5.2% | hardness, creamy lather |
| ricinoleic | 0% | conditioning, bubbly and creamy lather |
| oleic | 44.5% | conditioning |
| linoleic | 36.5% | conditioning |
| linolenic | 2.7% | conditioning |
Basis: USDA FDC SR Legacy 171012, converted to % of total fatty acids.
Soap-quality scores (this oil alone)
| Hardness | 16 |
|---|---|
| Cleansing | 0 |
| Conditioning | 84 |
| Bubbly lather | 0 |
| Creamy lather | 16 |
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: 191.45 mg KOH/g (Median of sources' mgKoh_mid (no Codex/pharmacopoeia standard found)), from Codex Alimentarius CXS 210-1999, Standard for Named Vegetable Oils (Table 2: chemical and physical characteristics), FAO/WHO Codex Alimentarius Commission. Printed value: 189-195 (unhydrogenated soya bean oil) mg KOH/g.
Published values we checked:
- NaOH 0.1361 / KOH 0.1917 g alkali per g oil — Certified Lye
- 189-195 (unhydrogenated soya bean oil) mg KOH/g — FAO/WHO Codex Alimentarius Commission
Fatty acids: USDA FoodData Central, SR Legacy 171012: Oil, soybean, salad or cooking, (partially hydrogenated), USDA Agricultural Research Service.
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 .