title: Sample preparation methods for beeswax characterization by gas chromatography with flame ionization detection.
abstract: New and simpler methods of sample preparation to determine several families of compounds in beeswax by conventional and high temperature gas chromatography are proposed. To analyze hydrocarbons and palmitates, a dilution of sample is enough whereas for the total acid content, a hydrolysis and simultaneous methylation with BF3-methanol results more effective than the usual methods; for the total content of alcohols, a further acetylation with acetic anhydride is necessary. Free alcohols are directly acetylated in a sample dissolution but for free acids and monoesterified 1,2,3-propanetriols analysis, a previous extraction with acetonitrile is required. The concentrations of all the compounds studied are expressed in weight percentage referred only to one standard: octadecyl octadecanoate. The precision of the analytical methods has been evaluated showing its importance in the analysis of beeswaxes used in apiculture.
authors.affiliation: Department of Analytical Chemistry, Faculty of Sciences, University of Valladolid, Prado de la Magdalena s/n, Valladolid, Spain. jjimenez@qa.uva.es
authors.forename: J J
authors.initials: JJ
authors.lastname: Jiménez
authors.forename: J L
authors.initials: JL
authors.lastname: Bernal
authors.forename: M A J
authors.initials: MA
authors.lastname: del Nozal
authors.forename: M A T
authors.initials: MA
authors.lastname: Martín
authors.forename: J
authors.initials: J
authors.lastname: Bernal
mesh_terms: D000438:Alcohols / Q000032:analysis / Q000737:chemistry; D002849:Chromatography, Gas / Q000379:methods*; D005410:Flame Ionization / Q000379:methods; D006838:Hydrocarbons / Q000032:analysis / Q000737:chemistry; D010168:Palmitates / Q000032:analysis / Q000737:chemistry; D015203:Reproducibility of Results; D014885:Waxes / Q000032:analysis / Q000737:chemistry*
chemical_list: D000438:Alcohols; D006838:Hydrocarbons; D010168:Palmitates; D014885:Waxes; C038228:beeswax