essential oils are present in fruit flavedo in great quantities.
This layer consists of the epidermis covering the exocarp
consisting of irregular parenchymatous cells, which are
completely enclosing numerous glands or oil sacs. Citrus
essential oils are a mixture of volatile compounds and mainly
consisted of monoterpene hydrocarbons (Sawamura et al.,
2004). Citrus oils are mixtures of over a hundred compounds
that can be approximated into three fractions: terpene
hydrocarbons, oxygenated compounds and non-volatile
compounds. The terpene fraction can constitute from 50 to
more than 95% of the oil; however, it makes little contribution
to the flavor and fragrance of the oil.