The citrus essential oil is mostly analyzed using different equipment such as gas chromatography (GC)-flame ionization detector (FID) and GC-MS. The GC-MS analyses of citrus peel components are usually carried out on chromatogram equipped with computerized data processing system of different models. The components identification is based on GC retentions, computer matching with NBS library.
The composition of the essential oil varies depending on the ripeness of fruits, storage conditions and extraction methods. It contains 85-99% volatile and 1-15% non-volatile components. Almost 200 different chemicals compounds were described from orange out of them about 100 had been identified. About 35 major components were identified from citrus reticulate and the major components were limonene(46.7%), geranial(19.0%), neral(14.5%), acetate geranyl(3.9%), geraniol(3.5%), β-caryophylle(2.6%), nerol(2.3%), citronellal(1.3%) and neryl acatate(1.1%).