On the genuineness of citrus essential oils. Part XLI. Italian bitter orange essential oil: Composition and detection of contamination and additions of oils and terpenes of sweet orange and of lemon

The composition of the volatile fraction of Italian bitter orange essential oil, camed out by LC, HRGC and GC-MS, is reported: 60 components have been identified. The results obtained are compared with those in the literature for Italian and Spanish bitter orange oils. Two methods are suggested which allows the detection of contamination or possible additions of terpenes and oils of sweet orange and of lemon to genuine bitter orange oil. One is based upon the content of delta-3-carene and the value of the ratios delta-3-carenelcamphene and delta-3-carenelterpinolene which permits the detection of the additions of 5% of sweet orange terpenes and oils; the second is based upon the content of alpha-terpinene and the value of the ratios alpha-terpinenelcamphene and alpha-terpinenelcis-beta-ocimene and allows the detection of the addition of even 3% of lemon terpenes and oils.