Olio di pracaxi
Nome INCI: Pentaclethra Macroloba Seed Oil.
Valori pubblicati
| Indice di saponificazione | 180 mg KOH/g |
| Usato dal calcolatore | 180,0 mg KOH/g (tipico) |
| SAP per NaOH | 0,1283 g/g |
| Numero di iodio | 68 g I₂/100 g |
| INS (SAP − numero di iodio) | 112 |
| Punto di fusione | 18,5 °C |
| Sostanze insaponificabili | — |
Una saponetta 100 % olio di pracaxi
Qualità convenzionali sommate a partire dai gruppi di acidi grassi; una saponetta di un solo olio è un punto di riferimento, non una ricetta.
Profilo degli acidi grassi
| Acido grasso | Intervallo pubblicato, % | Usato | |
|---|---|---|---|
| Acido palmitico | C16:0 · saturi | 1,7464–2,3103 (tipico 2,1946) | 2,2 |
| Acido palmitoleico | C16:1 | 0,0734–0,0856 (tipico 0,0734) | 0,1 |
| Acido stearico | C18:0 · saturi | 2,5301–3,102 (tipico 2,5301) | 2,5 |
| Acido oleico | C18:1 | 58,6091–59,4308 (tipico 59,4308) | 59,4 |
| Acido linoleico | C18:2 | 7,9605–9,1528 (tipico 9,1528) | 9,2 |
| Acido α-linolenico | C18:3 n-3 | 0,0643–0,3205 (tipico 0,0643) | 0,1 |
| Acido arachidico | C20:0 · saturi | 0,7677–2,5002 (tipico 0,7677) | 0,8 |
| Acido beenico | C22:0 · saturi | 13,5324–14,7712 (tipico 13,5324) | 13,5 |
| Acido erucico | C22:1 | 0,8051–0,9401 (tipico 0,9401) | 0,9 |
| Acido lignocerico | C24:0 · saturi | 9,9696–11,2723 (tipico 11,1544) | 11,2 |
Da dove vengono questi numeri
Le note con fonte qui sotto, e i titoli dei documenti che citano, restano nella lingua originale. Una citazione tradotta non si può rintracciare, e un riassunto tecnico tradotto non è più il riassunto che è stato verificato sul documento.
Table 2 'Propriedades fisico-quimicas e fisicas de oleo de pracaxi': saponification index 180 mg KOH/g, iodine index 68.0 g I2/100 g, melting point 18.5 C, solidification point 14.4 C, acidity 3.36 % as oleic, density 0.9173 at 15 C, Reichert-Meissl 2.6, Polenske 0.7. The table credits Pesce (2009), 'Oleaginosas da Amazonia'. Open-access PDF read in full.
Table 3, fatty-acid composition of fixed oil from P. macroloba seeds by GC-FID, three populations (Sao Domingos do Capim, Marituba, Belem). Source of the whole fatty-acid profile in this record. No saponification or iodine value reported.
Aggregated fatty-acid ranges over six GC/GC-MS studies (Costa, Bezerra, Lima, Pereira, Serra, Teixeira): palmitic 1.43-1.95, stearic 2.68-5.09, oleic 47.30-53.55, linoleic 11.70-13.05, linolenic 0.13-1.23, behenic 16.13-22.60, lignoceric 10.44-12.49, lauric 0.10-1.20, myristic 0.09-0.71, arachidic 1.0-12.30. Also reports a DSC melting transition of 11.90-14.68 C and that the oil is fully liquid above 20 C with fat crystals at 4-10 C. Cited here for the behenic disagreement only; not merged into the profile.
The numbers a calculator needs come from the EMBRAPA chapter on Pentaclethra macroloba in 'Plantas para o Futuro - Regiao Norte' (Cruz and Gurgel, MMA 2022, Serie Biodiversidade 53), whose Table 2 reprints Pesce's Amazonian oleaginous-plant measurements: saponification value 180 mg KOH/g, iodine value 68.0 g I2/100 g, melting point 18.5 C, solidification point 14.4 C, acidity 3.36 % as oleic acid, density 0.9173 at 15 C. The same table lists 47-53 C figures under 'ponto de fusao dos acidos graxos' and 'ponto de congelamento'; those are the titre of the isolated fatty acids and must not be read as a melting point for the fat, and the refractive index it prints (53.9 at 40 C) is on the Zeiss scale rather than nD. The fatty-acid profile is Correia et al. 2023 (International Journal of Food Science 2023:1446972), Table 3, GC-FID on seeds from three wild populations in Para. 'typical' is the Marituba column, the only one in which all twelve compounds were detected; min/max span Sao Domingos do Capim, Marituba and Belem. Margaric acid (C17:0, 0.0405 %, Marituba only) and tricosanoic acid (C23:0, 0.119-0.136 %) are dropped for want of a schema key, so the profile sums to 99.84 % rather than 100. The published pair is unusually well matched to that composition: by stoichiometry the Marituba profile implies 179.4 mg KOH/g against the 180 measured, and 70.9 g I2/100 g against the 68.0 measured. The reason the value sits near 180 rather than the 190-195 an ordinary oleic oil gives is behenic plus lignoceric acid, which together are about a quarter of the fat; lye demand falls as the chains lengthen, so pracaxi needs meaningfully less alkali than its oleic content suggests. Behenic content is where the sources disagree. Correia et al. measured 13.53-14.77 %, whereas the review of six earlier GC studies in Plants 2023 (12:1330) aggregates behenic at 16.13-22.60 %, lignoceric 10.44-12.49 % and oleic 47.30-53.55 %. Those are ranges over six different oils and cannot be merged into one profile without inventing a sample nobody measured, so they are not used; a maker working from a high-behenic lot should expect a saponification value a few points below 180, not above it. One practical trap: EMBRAPA records that pracaxi oil is liquid at room temperature but releases a large white solid fraction after time in storage, so an unmixed bottle pours something other than the lot it came from - warm and homogenise before weighing. Unsaponifiable matter is not reported in either document. INCI not verified against CosIng in this session, left null.
Questa scheda fa parte della database aperto degli ingredienti (ODbL). Hai trovato un errore o una fonte primaria migliore? Il dataset è su GitHub; le correzioni con il link a un documento sono benvenute.