Graisse d'ours
Nom INCI : Bear Oil. Aussi : Huile d'ours.
Calculer un savon 100 % graisse d'ours
C’est de la stœchiométrie sur une composition mesurée, pas une supposition, et c’est à peu près aussi bien cerné qu’une valeur publiée : vérifiée contre les 35 huiles du Codex où les deux champs viennent de la même norme, l’erreur médiane de la méthode est de 0,90 % et son 90e centile de 2,74 %, sans biais notable. La page des formules montre le calcul. Si vous avez un certificat d’analyse pour votre lot, entrez sa valeur mesurée dans le calculateur et cette estimation est mise de côté.
Valeurs publiées
| Indice de saponification | non publié |
| Dérivé de la composition | 195,2 ± 3 % mg KOH/g |
| Utilisé par le calculateur | 195,2 mg KOH/g (dérivé) |
| Indice pour le NaOH | 0,1391 g/g |
| Indice d’iode | — |
| INS (SAP − indice d’iode) | — |
| Point de fusion | — |
| Matière insaponifiable | — |
Un savon fait à 100 % de graisse d'ours
Qualités conventionnelles additionnées à partir des groupes d’acides gras ; un savon à une seule huile est un repère, pas une recette.
Profil d’acides gras
| Acide gras | Plage publiée, % | Utilisé | |
|---|---|---|---|
| Acide myristique | C14:0 · saturés | 0,61–1,93 (typique 1,21) | 1,2 |
| Acide palmitique | C16:0 · saturés | 12,35–45,01 (typique 25,33) | 25,3 |
| Acide stéarique | C18:0 · saturés | 4,75–18,73 (typique 8,65) | 8,7 |
| Acide oléique | C18:1 | 23,62–50,07 (typique 39,63) | 39,6 |
| Acide linoléique | C18:2 | 2,94–39,79 (typique 22,81) | 22,8 |
| Acide α-linolénique | C18:3 n-3 | 0–2,53 (typique 1,08) | 1,1 |
D’où viennent ces nombres
Les notes sourcées ci-dessous, ainsi que les titres des documents qu’elles citent, sont conservées dans leur langue d’origine. Une référence traduite ne peut plus être retrouvée, et un résumé technique traduit n’est plus le résumé qui a été vérifié par rapport au document.
Table 2 'Fatty acid composition (mass % of total fatty acids) of 13 black bears killed in Colorado during spring and summer, 2004' (individual rows, mean and SE); Table 1 (sex, age, date, cause of death); Study area and methods; Results. Read with pdftotext; the -layout output misplaces the cis 18:1n-9 column, so the rows were read from the -raw output, where each row is intact.
Table 3 (fatty-acid group ratios and SFA of white adipose tissue) and the descriptions of Supplementary Tables S1-S2. Read through the Europe PMC JATS XML; no percent-of-total-fatty-acid profile is printed, so no figure is used.
Tables 2 and 3 (GC-MS fatty-acid composition of bear grease by simmering and by enzymatic digestion). Read through the Europe PMC JATS XML and rejected: peaks labelled 'analytical standard' and '9,12-octadecadiynoic acid'.
SOURCE: Thiemann, Stahl, Baruch-Mordo & Breck, 'Trans fatty acids provide evidence of anthropogenic feeding by black bears', Human-Wildlife Conflicts 2(2):183-193 (2008), Table 2: subcutaneous fat (a minimum 1-2 cm3 from the mid-section) of 13 American black bears (Ursus americanus) killed in western Colorado in late spring and summer (May-September) 2004 - 6 destroyed after breaking into dwellings or killing livestock, 5 in the road-kill category (one of them shot after being struck by a vehicle), 1 cub found dying of possible poisoning (category 'injury') and 1 hunter harvest; 8 males and 5 females, 0-12 years where aged; modified Folch extraction, HCl-methanol methylation, GC-MS on an Agilent HP-88 column with a 13:0 internal standard; mass % of total fatty acids. Only nine acids were identified, and 16:0, 18:0, cis 18:1n-9 and cis 18:2n-6 made up more than 95 % of every sample. 'typical' is the printed mean of the 13 bears; min/max are the extremes of the printed individual rows: 14:0 mean 1.21 (0.61 bear 4 - 1.93 bear 8), 16:0 25.33 (12.35 bear 4 - 45.01 bear 6), 18:0 8.65 (4.75 bear 10 - 18.73 bear 3), cis 18:1n-9 39.63 (23.62 bear 9 - 50.07 bear 13), cis 18:2n-6 22.81 (2.94 bear 3 - 39.79 bear 7), 18:3n-3 1.08 (0.00 bear 8 - 2.53 bear 9); SE of the means 0.11, 2.65, 0.98, 1.94, 3.73, 0.24. NOT MAPPED: trans 18:1n-9 mean 1.13 (0.00-2.53), trans 18:2n-6 0.14 (0.00-1.44), 20:3n-3 0.02 (0.00-0.13) - 1.29 % of the mean; elaidic acid is deliberately not folded into oleic. Mapped keys total 98.71 % of the mean. Palmitoleic acid (16:1) was not among the nine acids identified, so the record has no palmitoleic entry; if the fat carried some, the shares printed for the other acids are correspondingly high. DIET DRIVES THIS FAT. A bear is a monogastric omnivore and lays down dietary fatty acids with little change: linoleic acid runs from 2.94 to 39.79 % between individual bears, and the conflict bears, which had eaten human food, carried more trans fat (trans 18:1n-9 1.60 +/- 0.30 % against 0.73 +/- 0.34 % in the others). A bear fattened in autumn on mast, berries or fish will not match this summer sample. NO SAPONIFICATION VALUE, IODINE VALUE, MELTING POINT OR UNSAPONIFIABLE MATTER could be sourced; this paper measured none. Also checked: Giroud et al., Front. Physiol. 10:389 (2019), subcutaneous white adipose tissue of Scandinavian brown bears (Ursus arctos) in summer and in hibernation - the article tables give only fatty-acid group ratios (WAT SFA 44.08 % summer, 37.49 % winter) and its supplementary tables give concentrations (mmol/l) and proportions within the SFA, MUFA and PUFA classes, not percent of total fatty acids, so nothing is transcribed from it. Wang et al., Molecules 29(6):1311 (2024), bear grease of farmed Asiatic black bears (Selenarctos thibetanus) rendered by simmering or enzymatic digestion - read and rejected: its GC-MS tables label the largest peak 'analytical standard' (35.88 and 36.99 %) and list '9,12-octadecadiynoic acid' (16.76 and 15.26 %), a misidentification, and name neither oleic nor stearic acid, so the composition cannot be mapped (the same tables give palmitoleic 9.80 and 9.97 % and palmitic 19.75 and 19.7 %). Paywalled and not read: Can. J. Zool. (2001) 'Variation in the chemical composition of adipose tissue of three species of ursids' (DOI 10.1139/z01-101); Physiol. Biochem. Zool. (2017) on the subcutaneous adipose lipids of Croatian brown bears (DOI 10.1086/690913); J. Comp. Physiol. B (2021) on feeding and fasting bears (DOI 10.1007/s00360-021-01414-5). The calculator will derive a saponification value from the typical profile and label it derived. INCI is CosIng's entry for Bear Oil ('the oil derived from bear fat that has been boiled and filtered (Ursidae)'), which names no species; CosIng gives it no CAS or EC number.
Cette fiche fait partie de la base d’ingrédients ouverte (ODbL). Vous avez trouvé une erreur ou une meilleure source primaire ? Le jeu de données est sur GitHub ; les corrections accompagnées d’un lien vers un document sont bienvenues.