Assessment of free plant sterols in cold pressed Citrus essential oils

A fast, sensitive, accurate and robust GC-FID and confirmatoryGC-MS method, was developed to simultaneously determinesqualene and underivatized free plant sterols in Citrus essentialoils (cEOs). The method was applied to assess the content ofsqualene and free plant sterols in four most commonly employedcold-pressed cEOs (bergamot, lemon, mandarin and orange). cEOsplant sterols exhibited distinctive molecular patterns, with levelsranging from 182 to 1100mg kg1 in lemon and bergamot essentialoils, respectively. b-sitosterol was the dominant compound inall cases, with an average content of 650mg kg1 in bergamotand orange essential oils. Campesterol and brassicasterol occurredat much lower amount in all samples. Bergamot essential oil wasalso the richest in squalene (537mg kg1) compared to the othercEOs. The method developed could contribute to define compositionalpatterns of cEOs, thus supporting their versatile utilisationin the food and flavour industry.