Plum kernel oil: SAP value and fatty acids
Plum kernel oil has a saponification value of 190 mg KOH/g. One gram needs 0.135 g of sodium hydroxide (NaOH) for bar soap or 0.190 g of potassium hydroxide (KOH) for liquid soap to turn fully into soap, before any superfat.
Key numbers
- SAP, NaOH
- 0.135448 g per g oil
- SAP, KOH
- 0.19 g per g oil
- Saponification value
- 190 mg KOH/g
- Iodine value
- 105
- INS
- 85
- INCI name
- Prunus Domestica Seed Oil
Example: 100 g of Plum kernel oil with no superfat needs 13.5 g of 100% NaOH, or 19.0 g of 100% KOH. A 5% superfat uses 5% less.
In soap
Its main fatty acids in our cited profile are oleic (72.7%) and linoleic (16.4%). The eight fatty acids used in soap-quality scores make up 97.8% of the profile.
On its own it scores 9 for hardness, 0 for cleansing and 89 for conditioning, with a saturated : unsaturated split of 9 : 89.
Only one specification with a number was found, and its range is wide. A 2015 paper (Özcan et al., Quality Assurance and Safety of Crops & Foods, doi:10.3920/QAS2013.0319) gives 170–195 for eight fruit kernels together, not plum alone, so it is not used. Check your supplier's COA. Only one published source was found for this value; confirm it against your supplier's certificate of analysis.
Fatty-acid profile
| Fatty acid | % of fatty acids | Counts toward |
|---|---|---|
| lauric | 0% | hardness, cleansing, bubbly lather |
| myristic | 0% | hardness, cleansing, bubbly lather |
| palmitic | 5.7% | hardness, creamy lather |
| stearic | 2.9% | hardness, creamy lather |
| ricinoleic | 0% | conditioning, bubbly and creamy lather |
| oleic | 72.7% | conditioning |
| linoleic | 16.4% | conditioning |
| linolenic | 0.1% | conditioning |
Basis: Rodríguez-Blázquez et al. 2023 Table 3, plum (Prunus domestica) kernel oil; lauric/myristic not reported, recorded as 0.
Soap-quality scores (this oil alone)
| Hardness | 9 |
|---|---|
| Cleansing | 0 |
| Conditioning | 89 |
| Bubbly lather | 0 |
| Creamy lather | 9 |
| Iodine | 105 |
| INS | 85 |
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: 190 mg KOH/g (Median of sources' mgKoh_mid (no Codex/pharmacopoeia standard found)), from Plum seed oil, organic, cold pressed (product page with specification), Skinchakra (German cosmetic oil supplier). Printed value: 170-210 mg KOH/gr mg KOH/g.
Published values we checked:
Fatty acids and iodine: Rodríguez-Blázquez S. et al. (2023) Valorization of Prunus Seed Oils: Fatty Acids Composition and Oxidative Stability. Molecules 28:7045. doi:10.3390/molecules28207045, MDPI (open access, peer-reviewed). Also checked: Skinchakra (German cosmetic oil supplier).
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 .