title: Changes of the wax contents in mixtures of olive oils as determined by gas chromatography with a flame ionization detector.
abstract: Mixing of refined olive-pomace oil with virgin olive oil is a fraud that has been tried often. Normally, the tests that detected the fraud were determinations of wax esters, erythrodiol+uvaol, and stigmastadienes contents. The most common is the determination of wax esters content (extra virgin olive oil is very poor in wax esters, usually less than 100 mg/kg). In this work, the variations of individual wax esters (C40, C42, C44, and C46), with different degrees of unsaturation content, and total wax esters were studied when extra virgin olive oil and refined pomace-olive oil were mixed. The following mixtures were prepared: extra virgin olive oil plus 1, 2, 4, 6, 8, 10, 12, 15, 18, 25, 35, 45, 50, and 80% of refined olive-pomace oil. In all cases, individual and total wax ester content variation was linear with increasing percentage of refined olive-pomace oil in the mixture. The variation of the total wax esters content can be adjusted according to the equation: Total wax esters, mg/kg = 14.3 x (% refined olive-pomace oil) + 83.9.
authors: University of Pablo de Olavide, Molecular Biology and Biochemical Engineering Department, 41013 Seville, Spain. ghodaifa@upo.es
authors: Gassan
authors: G
authors: Hodaifa
authors: Leopoldo
authors: L
authors: MartínezNieto
authors: Juan L
authors: JL
authors: Lozano
authors: Sebastián
authors: S
authors: Sánchez
mesh_terms: D000465:Algorithms; D002849:Chromatography, Gas; D004952:Esters / Q000032:analysis; D005410:Flame Ionization; D005506:Food Contamination / Q000032:analysis; D005607:Fraud; D008970:Molecular Weight; D009828:Oleanolic Acid / Q000031:analogs & derivatives / Q000032:analysis; D000069463:Olive Oil; D010938:Plant Oils / Q000032:analysis* / Q000737:chemistry; D014315:Triterpenes / Q000032:analysis; D014885:Waxes / Q000032:analysis*
chemical_list: D004952:Esters; D000069463:Olive Oil; D010938:Plant Oils; D014315:Triterpenes; D014885:Waxes; C077953:erythrodiol; D009828:Oleanolic Acid; C013330:uvaol