essential oil

n. A volatile oil, usually having the characteristic odor or flavor of the plant from which it is obtained, used to make perfumes and flavorings.

essential oil

n (Elements & Compounds) any of various volatile organic oils present in plants, usually containing terpenes and esters and having the odour or flavour of the plant from which they are extracted: used in flavouring and perfumery. Compare fixed oil See also oleoresin

essen′tial oil′

n. any of a class of volatile oils obtained from plants, possessing the odor and other characteristic properties of the plant: used in perfumes, flavors, and pharmaceuticals. [1665–75]

Thesaurus

Noun

essential oil - an oil having the odor or flavor of the plant from which it comes; used in perfume and flavoringsvolatile oililang-ilang - oil distilled from flowers of the ilang-ilang tree; used in perfumerybitter almond oil - pale yellow essential oil obtained from bitter almonds by distillation from almond cake or mealatar, athar, attar, ottar - essential oil or perfume obtained from flowersclove oil, oil of cloves - essential oil obtained from cloves and used to flavor medicinescostus oil - a yellow volatile essential oil obtained from costusroot; used in perfumeseucalyptus oil - an essential oil obtained from the leaves of eucalyptsoil of turpentine, spirit of turpentine, turps, turpentine - volatile liquid distilled from turpentine oleoresin; used as paint thinner and solvent and medicinallyabsinthe oil, wormwood oil - a dark bitter oil obtained from wormwood leaves; flavors absinthe liqueurslinalool - a colorless fragrant liquid found in many essential oilsoil - a slippery or viscous liquid or liquefiable substance not miscible with water

essential oil

any of various volatile organic oils present in plants, usually containing terpenes and esters and having the odour or flavour of the plant from which they are extracted: used in flavouring and perfumery

Essential Oil

an odorous substance that imparts the characteristic odor of the plant from which it is derived. Essential oils are synthesized in special cells of various plant organs. The biological role of the oils has not been confirmed, but it is assumed that they reduce heat loss and serve as attractants or repellents.

Essential oils are multicomponent mixtures of organic compounds, mostly terpenes and their oxygen derivatives (alcohols, aldehydes, ketones, ethers, and esters). In some cases, only one or a few components predominate. For example, more than 200 organic compounds have been found in rose oil, but beta-phenyl-ethyl alcohol and terpene alcohols (geraniol, linalool, citronellol, and nerol) account for 80 percent of the oil’s mass. Peppermint oil has more than 100 compounds, but menthol, menthone, menthyl acetate, and cineole constitute more than 90 percent of the mass. The composition of essential oils often changes markedly during the development of a plant. For example, coriander oil obtained from flowers contains as much as 80 percent decyl aldehyde, whereas coriander oil derived from seeds contains 60–80 percent linalool.

Essential oils are transparent colorless or colored (yellow, green, or red-brown) liquids. In contrast to vegetable oils, many essential oils are volatile. Their density, as a rule, is less than 1.0. The oils are virtually insoluble in water, but they readily dissolve in ether, petroleum ether, benzene, and other low-polarity organic solvents. Essential oils are optically active. They are gradually oxidized and become resinous by the action of light and atmospheric oxygen, resulting in a change in odor.

Essential oils have been known since antiquity. They have been used in incense, cosmetic preparations, medicinal drugs, and embalming agents.

Of the approximately 3,000 plant species that contain essential oils, about 1,000 are found in the USSR. Only 150 to 200 species have industrial importance. Most essential oils are obtained from tropical and subtropical plants; only a few essential-oil plants, for example, coriander and anise, are cultivated in the temperate zone. In 1976, world production of essential oils was about 25,000 tons. Only a relatively few oils—citrus, citronella, lemongrass, peppermint, coriander, anise, and oil of cloves—are produced on a large scale of no less than 1,000 tons annually. The oil is obtained from raw (geranium, basil), dried (coriander leaves, the roots of sweet flag), or fermented (iris roots, oakmoss) plant material.

Steam distillation is the most common method for obtaining essential oils. Modifications of the method include the treatment of plant material with “dry steam.” The mixture of essential-oil vapors and water is condensed, and the oily layer is separated. For more complete extraction of the essential oils, the aqueous distillation layer is treated with active carbon or a highly volatile solvent, for example, ether.

Essential oils whose main components would decompose under the relatively vigorous conditions of steam distillation are obtained by extraction with organic liquids (for example, petroleum ether or benzene) or with liquified gases (for example, carbon dioxide). Extraction is used in the production of essential oils from jasmine flowers and iris roots. The residue after distilling off the solvent is usually a waxy or oily mass, which is treated with alcohol, usually by boiling. The solution obtained is cooled and filtered to remove waste matter. The essential oils remaining after removal of the alcohol solvent are said to be pure, or absolute.

Expression is used for the derivation of oils from the rinds of citrus fruits. Also common is enfleurage, a method by which the oil evaporating from flowers is absorbed by pure, scentless lard or beef fat applied in a thin film on a glass plate. Essential oils are extracted from the fragrant mass with a solvent. Maceration, a procedure involving the pouring of fat heated to 50°–70°C onto the flowers, yields low-quality oil and is rarely used.

The unavailability of some natural essential oils has led to their replacement by artificial compositions based on synthetic fragrances (artificial or synthetic oils).

Essential oils are used mainly in the perfume and cosmetics industry, where they serve as the raw material in the production of fragrances (menthol, citral, eugenol, geraniol, linalool). Some essential oils (peppermint, eucalyptus, and anise oils) are used in medicine, and some are used in the food, confectionery, and canning industries (peppermint, anise, orange, lemon, and mandarin oils). In these cases, the relatively toxic terpene hydrocarbons are removed by distillation or treatment with alcohol.

REFERENCES

Goriaev, M. I. Efirnye masla flory SSSR. Alma-Ata, 1952.
Koral’nik, S. I., and L. Iu. Neiman. Sovremennye resursy i osobennosti proizvodstva efirnykh masel. Moscow, 1973.
Guenther, E. The Essential Oils, vols. 1–6. New York, 1948–52.

V. N. FROSIN

essential oil

[i′sen·chəl ′ȯil] (materials) Any of the odoriferous oily products of plant origin which are distillable; the principal constituents are terpenes, but benzenoid and aliphatic compounds may also be present. Also known as ethereal oil.

essential oil

oil

[oil] 1. an unctuous, combustible substance that is liquid, or easily liquefiable, on warming, and is not miscible with water, but is soluble in ether. Such substances, depending on their origin, are classified as animal, mineral, or vegetable oils. Depending on their behavior on heating, they are classified as volatile or fixed. For specific oils, see under the name, as castor oil.2. a fat that is liquid at room temperature.essential oil volatile o.expressed oil (fatty oil) (fixed oil) one that is not volatile, i.e., does not evaporate on warming; such oils consist of a mixture of fatty acids and their esters, and are classified as solid, semisolid, and liquid, or as drying, semidrying, and nondrying as a function of their tendency to solidify on exposure to air.volatile oil an oil that evaporates readily; such oils occur in aromatic plants, to which they give odor and other characteristics.

essential oil

Alternative medicine
An oil distilled or extracted from various plants (e.g., citrus fruits, eucalyptus, flowers, lavender, peppermint, rosemary, tea tree and others), which is used in aromatherapy.

es·sen·tial oil

(ĕ-sen'shăl oyl) A plant product, usually somewhat volatile, giving the odors and tastes characteristic of the particular plant; usually, the steam distillates of plants or of oils obtained by pressing the rinds of plants.
See also: volatile oil

Essential oil

A volatile oil extracted from the leaves, fruit, flowers, roots, or other components of a plant and used in aromatherapy, perfumes, and foods and beverages.Mentioned in: Aromatherapy

es·sen·tial oil

(ĕ-sen'shăl oyl) A plant product, usually somewhat volatile, giving the odors and tastes characteristic of the particular plant.

Patient discussion about essential oil

Q. Have you ever try Flower Essences for bipolar disorders??? I am Flower Essences practitioner as well as a Cognitive Behavior Therapist educated in Venezuela.I have wonderful experiences with Flower Essences and Alternative Terapies.A. i never tried flower essence in any medical situation. maybe i will, i think it's worth a try. but about Bipolar disorder- changing medications that work and, even though they have unpleasant side effects, proven to help- could have destructive outcome. so in this case i don't think that it's wise to do so.

More discussions about essential oil

essential oil

noun

Synonyms for essential oil

noun an oil having the odor or flavor of the plant from which it comes

Synonyms

volatile oil

Related Words

ilang-ilang
bitter almond oil
atar
athar
attar
ottar
clove oil
oil of cloves
costus oil
eucalyptus oil
oil of turpentine
spirit of turpentine
turps
turpentine
absinthe oil
wormwood oil
linalool
oil