Cera de myrica
Nombre INCI: Myrica Cerifera (Bayberry) Fruit Wax. También: Cera de bayberry.
Valores publicados
| Índice de saponificación | 188–225 mg KOH/g |
| Usado por la calculadora | 206.5 mg KOH/g (punto medio) |
| SAP para NaOH | 0.1472 g/g |
| Índice de yodo | — |
| INS (SAP − índice de yodo) | — |
| Punto de fusión | 40–55 °C |
| Materia insaponificable | — |
Una pastilla hecha 100 % de cera de myrica
Cualidades convencionales sumadas a partir de los grupos de ácidos grasos; una pastilla de un solo aceite es una referencia, no una receta.
Perfil de ácidos grasos
| Ácido graso | Rango publicado, % | Usado | |
|---|---|---|---|
| Ácido mirístico | C14:0 · saturados | ≤ 25 | 25.0 |
| Ácido palmítico | C16:0 · saturados | ≥ 75 | 75.0 |
| Ácido esteárico | C18:0 · saturados | ≤ 1 | 1.0 |
De dónde salen estos números
Las notas con fuente que aparecen debajo, y los títulos de los documentos que citan, se mantienen en su idioma original. Una cita traducida no se puede consultar, y un resumen técnico traducido ya no es el resumen que se contrastó con el documento.
Chemical Properties table: Melting Point, method USP 741, 40-55 C; Saponification Value, method USP 401, 188-225 mg KOH/g; Color, visual, Light Brown to Olive Green. Regulatory: INCI Myrica Cerifera (Bayberry) Fruit Wax, CAS 8038-77-5, EINECS not assigned, manufactured Watertown, Connecticut. Page text describes the wax as consisting predominantly of triglycerides with C-16 carbon chain lengths and the shrub as native to Central and South America. No iodine value, acid value or fatty-acid composition is published.
Source of the fatty-acid profile. Surface wax acyl composition entirely saturated: C16:0 >75 %, C14:0 <25 %, C18:0 <1 %, no unsaturated acids detected. TAG:DAG:MAG molar ratio about 30:62:8. Wax is 32 % of fruit dry weight, 9.8 mg per fruit, 8.7 mg/cm2 of surface. Crystallisation above 40 C. Measured on Myrica pensylvanica, not on the M. cerifera named in the commercial INCI.
Read this one differently from the other waxes in the dataset. Beeswax, candelilla and carnauba are wax esters, hydrocarbons and alcohols, which is why their records carry no fatty-acid profile; bayberry wax is a glycerolipid, so it saponifies like a fat and a normal profile describes it. Simpson and Ohlrogge (The Plant Cell, 2016, doi 10.1105/tpc.15.00900) analysed the surface wax of Myrica pensylvanica fruit and found it entirely saturated acylglycerol - triacylglycerol, diacylglycerol and monoacylglycerol in a molar ratio of about 30:62:8 - with acyl composition C16:0 above 75 %, C14:0 below 25 % and C18:0 under 1 %, and no unsaturated acid detected at all; the wax is 32 % of the fruit's dry weight and crystallises above 40 C. The mostly-diacylglycerol structure is worth holding on to, because it explains the saponification value: a pure tripalmitin would titrate at 208 mg KOH/g, a dipalmitin at about 197 and a monopalmitin at 170, and a 30:62:8 mixture on this acyl composition works out near 205 - the middle of the producer's band, not the 208-215 a reader would predict from 'mostly palmitic triglyceride'. The recorded values are the producer specification for Koster Keunen Bayberry Wax (their code 188): melting point 40-55 C by USP <741>, saponification value 188-225 mg KOH/g by USP <401>, colour light brown to olive green, INCI Myrica Cerifera (Bayberry) Fruit Wax, CAS 8038-77-5. No iodine value, acid value or composition is published with it, so iodineValue is null; on the Plant Cell composition a fully saturated glyceride should measure close to zero. Two things will catch a maker out. First, species. The INCI names Myrica cerifera, the eastern North American bayberry, while the same producer's own page calls the shrub native to Central and South America, which is the Andean wax laurel (Morella pubescens) traded under the same name; the profile recorded here was measured on a third species, M. pensylvanica, because that is the analysis available in an allowed document. No primary analysis of M. cerifera or M. pubescens fruit wax was found - older compilations describe bayberry wax as myristic-dominant (around 58 % C14:0) rather than palmitic-dominant, which is more likely a species split than a contradiction, but none of them is a document this dataset may cite. So treat the profile as indicative of the palmitic-type material and the saponification value, which is measured on whatever is actually in the drum, as the number to calculate with. Second, the width of that number: 188-225 is plus or minus 9 % about its own centre, three times the spread of a Codex oil. At 5-10 % of a recipe that is a fraction of a percent of the total lye and a normal superfat absorbs it; at 30 % with a 3 % superfat it does not.
Esta ficha forma parte de la base de datos abierta de ingredientes (ODbL). ¿Ha encontrado un error o una fuente primaria mejor? El conjunto de datos está en GitHub; las correcciones con un enlace al documento son bienvenidas.