Original composition of marjoram flavor and its changes during processing

The composition of monoterpenes in essential oils or flavor extracts from marjoram (Majorana hortensis Moench) depends on the method applied for their isolation. Experiments with solvent extracts, with leaf material ground under liquid nitrogen, and with direct injections of the content of oil glands revealed the presence of a common precursor structure. The study of rearrangement reactions of sabinene hydrate and sabinene hydrate acetate confirmed that the sabinene hydrate skeleton represents the primary monoterpene structure in marjoram. Two activated forms are responsible for the formation of rearranged monoterpenes during workup of the plant material: a “bound” form, presumably (Z)—sabinene hydrate pyrophosphate, and a “free” form, (Z)—sabinene hydrate acetate, which is the main component in the oil glands together with (Z)—sabinene hydrate.