A simplified method for HPLC‐MS analysis of sterols in vegetable oil

Abstract We have developed a liquid‐chromatographic method using atmospheric pressure chemical ionization (APCI)‐mass spectrometry (MS) detection in positive mode. This method was used to separate and identify 15 sterols and 2 dihydroxy triterpenes in saponified oils, enabling the analysis of these compounds directly from saponified samples without recourse to thin‐layer chromatography; this fact thus significantly simplifies the process. The analyses were made using a Waters Atlantis 5 µm dC 18 150×2.1 mm column with a gradient of acetonitrile/water (0.01% acetic acid) at a flow rate of 0.5 mL/min and a column temperature of 30 °C. The quantification of several of these compounds in soybean oil, palm oil, seed oil, sunflower oil, olive‐pomace oil and virgin olive oil was carried out using their commercial standards, and the results were compared satisfactorily with the official method.