Résumé
A method was proposed for the separation and determination of paraffin waxes in food by HPLC-evaporative light scattering detection (ELSD). A normal-phase column was used to separate nonparaffinic and paraffinic materials without resolving the latter into individual components. The t-test method was adopted for the evaluation of mean difference between response factors of n-alkanes in paraffin waxes on ELSD detector. No mean difference was obtained between response factors, which can be used for quantitative determination of paraffin waxes in food. The determination results obtained by HPLC-ELSD were compared with those by GC-MS. The linear range for the determination of paraffin waxes was in the range from 10 to 500 mg/L with a correlation coefficient of 0.9988, and the limit of detection was 1.0 mg/L. With the spiking level of 10, 50 and 100 mg/kg, the recovery ranged from 84.6% to 105.4% and the relative standard deviation ranging from 5.4% to 7.2%. The proposed method is simple, fast and sensitive.