title: Microwave-assisted rapid determination of vitamins a and e in beverages.
abstract: A new rapid procedure for the determination of vitamins A and E in beverages has been developed and validated. Key steps include a microwave-assisted saponification of the sample and a single-step extraction of the vitamins prior to HPLC analysis. All sample preparation steps are carried out consecutively in the same vial. The vitamins are determined using normal-phase (Si-60) HPLC with fluorescence detection. The method is applicable to beverages with a content of all-trans-retinol >0.14 mg/L and/or a content of alpha-tocopherol >1 mg/L. Recoveries determined by spiking experiments ranged from 91.3 to 106.3%. The precision of the method is characterized by relative standard deviations of <2% for alpha-tocopherol and <5% for all-trans-retinol.
authors.affiliation: Human Nutrition and Health, Analytics (VFHA), Roche Vitamins Ltd., CH-4070 Basel, Switzerland.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Höller
authors.forename: Didier
authors.initials: D
authors.lastname: Wolter
authors.forename: Peter
authors.initials: P
authors.lastname: Hofmann
authors.forename: Volker
authors.initials: V
authors.lastname: Spitzer
mesh_terms: D001628:Beverages / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid; D008872:Microwaves; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014801:Vitamin A / Q000032:analysis*; D014810:Vitamin E / Q000032:analysis*; D024502:alpha-Tocopherol / Q000032:analysis
chemical_list: D014801:Vitamin A; D014810:Vitamin E; D024502:alpha-Tocopherol