In Persian nutrition culture, drinking aromatic waters (hydrosols, distillate) has a long history as functional beverages or therapeutic remedies. The co-distilled water with essential oils, which contains partial amounts of more water-soluble volatile compounds are diluted and used as beverages. Since the solubility of volatile components is different in water, the overall composition, and thus the biological activities of aromatic waters seem to be different from the essential oils they were co-distilled with. Despite the essential oils, chemical constituents of many aromatic waters have not been evaluated scientifically. This research investigated hydrosols used for mental and neurological health maintenance in Persian nutrition culture and their chemical constituents. Constitutions of these hydrosols were extracted by liquid/liquid extraction method and identified by gas chromatography–mass spectrometry. Furthermore, cluster analysis was used to evaluate the relevance of these hydrosols chemical constituents. About 93 compounds were identified from 20 aromatic waters. the major or second major constituents were thymol (azarol howthorn, frankincense, lemon balm, valerian, shadab), phenethyl alcohol (damask rose, dog-rose, starflower), carvacrol (basil, creeping buttercup, lemon balm); eugenol (shadab, dog-rose, starflower, basil), camphor (yarrow and wormwood), carvone (oriental plane), caryophyllene (cuminum), cinnamaldehyde (Chinese cinnamon), p-cymen-7-ol (musk willow), limonene (lemon verbena), linalool and α-terpineol (bitter orange), menthol (date palm) and methyl 5-vinylnicotinate (olive). Although, these hydrosols prepared from plants belong to different genus and families, but cluster analysis showed obvious similarities between their chemical constituents. Results of this investigation showed in many cases that the constituents of aromatic waters are different from the pure essential oil.
