First Determination of Glycidyl Ester Species in Edible Oils by Reverse-Phase Ultra-Performance Liquid Chromatography Coupled with an Evaporative Light-Scattering Detector

• Published in: Molecules (Basel, Switzerland) Vol. 26; no. 9; p. 2702
• Main Authors: Wu, Ping-Yi, Chen, Hsuan, Su, Nan-Wei, Chiou, Tai-Ying, Lee, Wei-Ju
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 05.05.2021; MDPI
• Subjects: Aqueous solutions; C18 column; Carbon; Chromatography; Coefficient of variation; edible oil; Edible oils; Esters; Fatty acids; Food safety; glycidyl ester species; Glycidyl esters; Light scattering; Liquid chromatography; Methods; Oils & fats; Olive oil; Quantitation; Retention; Sensors; Solvents; UPLC-ELSD; validation; Values
• ISSN: 1420-3049; 1420-3049
• DOI: 10.3390/molecules26092702

In this work, a new ultra-performance liquid chromatograph-evaporative light-scattering detector (UPLC-ELSD) method for quantitation of glycidyl esters (GE) contents in edible oils is presented. The method features complete separation of five GE species within 20 min by a C18 column and gradient elution with a mobile phase consisting of 85% and 2.5% methanol aqueous solutions. The coefficients of regression (R2) were all ≥0.9999 for the linear-quadratic regression curves of GE species in a concentration range of 5~80 μg/mL. The intraday and interday recoveries (%) of GE species in solvent were in a range of 81.3~107.3%, and the intraday and interday coefficients of variation (CVs, %) were all ≤8.6%. The average recovery (%) of GE species spiked in extra-virgin olive oil samples ranged from 88.3~107.8% and the intermediate precision (CV, %) of ≤14% indicated acceptable accuracy and precision. The method exhibited limit of quantification (LOQ) for each GE species (0.6 μg glycidol equivalents/g oil). The method was applied to determine GE concentrations of six commercial oil samples, and total glycidol equivalents were consistent with data obtained by GC-MS method. This UPLC-ELSD method could be adopted for precursory screening and research purposes to improve food safety when MS detectors are unavailable.