Herbs, oils from

The use of steam-distilled herb oil from whole plants is declining and few recent reports are available. The oil from fresh or wilted herbage is a nearly colourless to pale yellow mobile liquid, which may darken... 

Essential Oils. Volatile oils from plants are referred to as essential oils. The oils can be obtained through steam distillation, solvent extraction, or separation of the oils from pressed fmit. They consist of oxygenated compounds, terpenes, and sesquiterpenes. The primary flavor components of essential oils are oxygenated compounds. Terpenes contain some flavors but are often removed from the essential oil because they are easily oxidized (causiag off-flavors or odors) and are iasoluble. Essential oils are prepared from fmits, herbs, roots, and spices. 

MoTiarda Ustuiusa.—Thi-j plant is known in Xorth Aniorica an the wild hcigamot. The ft tsh herb yields from O d la f per cent, of essential oil,. inl the dried h irb, aboQt 2 7 por cent. 

The oils from the root and from the whole herb have also been examined and found to ha -c the following characters —... 

The uil distilled from the herb in herb oil, but is slightly laeio-routory. 

The dense fluid that exists above the critical temperature and pressure of a substance is called a supercritical fluid. It may be so dense that, although it is formally a gas, it is as dense as a liquid phase and can act as a solvent for liquids and solids. Supercritical carbon dioxide, for instance, can dissolve organic compounds. It is used to remove caffeine from coffee beans, to separate drugs from biological fluids for later analysis, and to extract perfumes from flowers and phytochemicals from herbs. The use of supercritical carbon dioxide avoids contamination with potentially harmful solvents and allows rapid extraction on account of the high mobility of the molecules through the fluid. Supercritical hydrocarbons are used to dissolve coal and separate it from ash, and they have been proposed for extracting oil from oil-rich tar sands. 

People have always been interested in the odour and use of essential oils (from herbs and spices). This is probably attributable to their aromas, and also to the bacteriostatic and antiseptic properties of many of the aroma chemicals they contain. While the use of essential oils is associated with mankind s history, the beginning of perfumery is more difficult to define. 

Gildemeister, E., Hoffmann, F., Die Atherischen Ole, Vol. Ilia, Akademie Verlag, Berlin, 1960, pp. 510-539 (Occurrence in more than 200 essential oils from herbs, leaves, flowers, and wood, review)-,... 

Lucchesi, M.E., F. Chemat, and J. Smadja. 2004. Solvent-free microwave extraction of essentials oil from aromatic herbs Comparison with conventional hydro-distillation. J. Chromatogr. A 1043 323-327. 

The herbs came from Portugal and had been sun dried but sufficient water remained in the dried stems and leaves to produce a volume of aqueous extracts which often exceeded that of the essential oils. Initial water contents for Rosemary and Thyme were 8.14% and 8.59% respectively. The residual water content after extraction were 1.85% for Rosemary and 3.53% for Thyme. 

Oregano Origanum virens L. is an perennial herb with 40-70 cm high and very aromatic. This plant grows in open and dry countries, at altitudes lower than 500-700 m. The major components of essential oil from Origanum virens L. are terpineol, a-pinene, camphor, thymol, carvacrol and cineole. Compounds such as alcohols and dipentene are also present. 

ARTHOICUM or PANNONIUM — A red oil from the roots of certain herbs obtained by their digestion with bread in horse-dung. 

Contrary to all literature rqxjrts major constituent reported here for the first time is trans-2-decenal, the content of which is relatively constant from living leaf to picked to commercial herb oil. TWo other alpha, beta unsaturated aldehydes, trans-2-dodecenal and trans-2-tetradecenal, both reported also for the first time, are present in appreciable quantities in both the living and dri leaf and at lower levels in the oil. A large nunher of related aldehydes and alcohols, both saturated and unsaturated, many reported for the... 

PROP From steam distilladon of aboveground parts (herb oil) or ripe seed (seed oil) o Petroselinium sativum Hoffm. (Fam. Umhelligerae). Yellow to light-brown liquid odor of parsley. D (herb oil) 0.908-0.940, (seed oil) 1.040 refr index (herb oil) 1.503-1.530 20°, (seed oh) 1.513-1.522 20°. Sol in fixed oils, mineral oU sltly sol in propylene glycol insol in glycerin. 

John W Parry University of Maryland, College Park, Maryland, Oils from Herbs, Spices, and Fruit Seeds. 

Oils from Herbs, Spices, and Fruit Seeds... 

OILS FROM HERBS, SPICES, AND FRUIT SEEDS... 

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