Bergamot essential oil and furanocoumarins. The main compounds in the oil are limonene, linalyl acetate, linalool, γ-terpinene and β-pinene, and in smaller quantities geranial and β-bisabolene. The main non-volatile compounds are coumarins (citropten, 5-geranyloxy-7-methoxycoumarin) and furanocoumarins (bergapten, bergamottin). The bergamot essential oil is particularly subject to adulteration being an essential oil produced in relatively small quantities. Generally adulteration is to "cut" the oil, i.e. adding distilled essences of poor quality and low cost, for example of bitter orange and bergamot mint and/or mixtures of terpenes, natural or synthetic, or "reconstruct" the essence from synthetic chemicals, coloring it with chlorophyll. Worldwide, each year, around
Bergamot essential oil three thousand tonnes of declared essence of bergamot are marketed, while the genuine essence of bergamot produced annually amounts to no more than one hundred tons. Natural source analysis based on the Carbon-14 method can identify adulterated essences by detecting synthetic chemicals manufactured from petroleum that are used to mimic the chemical profile of bergamot oil and other essential oils. Gas chromatography with columns having a chiral stationary phase allows analyzing mixtures of enantiomers. The analysis of the enantiomeric distribution of various compounds, such as linalyl acetate and linalool, allows the characterization of the bergamot oil according to the manufacturing