Clove essential oils steam distillation

Essentia.1 Oils. Essential oils (qv) are extracted from the flower, leaf, bark, fmit peel, or root of a plant to produce flavors such as mint, lemon, orange, clove, cinnamon, and ginger. These volatile oils are removed from plants either via steam distillation, or using the cold press method, which avoids heat degradation. Additional processing is sometimes employed to remove the unwanted elements from the oils, such as the terpenes in citms oils which are vulnerable to oxidation (49,50). 

Pimento Berry Oil. The pimento or allspice tree, Pimenta dioca L. (syn. P. officinalis, Liadl.), a native of the West Indies and Central America, yields two essential oils of commercial importance pimento berry oil and pimenta leaf oil. The leaf oil finds some use ia perfumery for its resemblance to clove leaf and cinnamon leaf oils as a result of its high content of eugenol. Pimento berry oil is an item of commerce with extensive appHcation by the flavor industry ia food products such as meat sauces, sausages, and pickles, and moderate use ia perfumery, where it is used primarily as a modifier ia the modem spicy types of men s fragrances. The oil is steam-distilled from dried, cmshed, fully grown but unripe fmits. It is a pale yellow Hquid with a warm-spicy, sweet odor with a fresh, clean topnote, a tenacious, sweet-balsamic-spicy body, and a tea-like undertone. A comparative analysis of the headspace volatiles of ripe pimento berries and a commercial oil has been performed and differences are shown ia Table 52 (95). 

Production. Since sufficient eugenol can be isolated from cheap essential oils, synthesis is not industrially important. Eugenol is still preferentially isolated from clove leaf and cinnamon leaf oil (e.g., by extraction with sodium hydroxide solution). Nonphenolic materials are then removed by steam distillation. After the alkaline solution is acidified at low temperature, pure eugenol is obtained by distillation. 

The use of terpenoids, usually as mixtures prepared from plants, dates from antiquity. The several essential oils produced by distillation of plant parts contained the plant essences. These oils have been employed in die preparation of perfumes, flavorings, and medidnals. Examples are oils of clove (local anesthetic in toothache), lemon (flavoring), lavender (perfume), and juniper (diuretic). Usually essential oil production depends on a simple technology which often involves steam distillation of plant material The perfume industry of Soudiem France uses somewhat more sophisticated procedures in the isolation of natural flower oils since these oils are heat sensitive. The separation of oils from citrus fruit residues m California and Florida is done by machine. 

The odor of a freshly crushed mint leaf, like many plant odors, is due to the presence in the plant of volatile C10 and Ci5 compounds, which are called terpenes. Isolation of these substances from the various parts of plants, even from the wood in some cases, by steam distillation or ether extraction gives what are known as essential oils. These are widely used in perfumery, as food flavorings and medicines, and as solvents. Among the typical essential oils are those obtained from cloves, roses, lavender, citronella, eucalyptus, peppermint, camphor, sandalwood, cedar, and turpentine. Such substances are of interest to us here because, as was pointed out by Wallach in 1887 and reemphasized by Ruzicka in 1935, the components of the essential oils can be regarded as derived from isoprene ... 

Volatile or essential oils are usually obtained from the appropriate plant material by steam distillation, though if certain components are unstable at these temperatures, other less harsh techniques such as expression or solvent extraction may be employed. These oils, which typically contain a complex mixture of low boiling components, are widely used in flavouring, perfumery, and aromatherapy. Only a small number of oils have useful therapeutic properties, e.g. clove and dill, though a wide range of oils is now exploited for aromatherapy. Most of those employed in medicines are simply added for flavouring purposes. Some of the materials are commercially important as sources of chemicals used industrially, e.g. turpentine. 

Clove oil may be obtained from cloves by steam distillation. A number of other spices may be used for extracting other oils (9,10) whose structures are shown in Table 16-1. The essential oils are rich in one main compound and since all components are UV absorbing, the fixed wavelength detector at 254 nm is adequate for detection. Liquid chromatography is a rapid analytical tool in analyzing the essential oils. 

The biggest market for essential oils is for perfumes, and, as might be expected, prices for these oils reflect their rarity. Recently, worldwide production of orange oil was 1500 tons and it sold for 0.75 per lb, while 400 tons of clove oil sold for 14.00 per lb, and 10 tons of jasmine oil sold for 2000 per lb. These three oils represent the most common extractive processes orange oil is obtained by expression (squeezing) of the peel in presses clove oil is obtained by steam distillation, as will be performed in this experiment and jasmine oil is obtained by extraction of the flower petals using ethanol. 

Since the work of Chfford et al., several studies of the small-scale extraction of essential components have been made and the work and methods have been reviewed [62-64]. Work has been carried out on eucalyptus [65] peppermint [66, 67], savory [67], laurel [68] and Thymbria spicata [69]. These reach similar conclusions to those made above for rosemary, wild marjoram and clove and in some cases comparisons with steam distillation and other methods have been made [58, 60, 61, 66, 68]. In addition to essential oil components, work is also being carried out on the extraction of compounds for analytical purposes [70, 71], including the extraction of metals [72, 73]. Other extractions of medical and industrial interest are being car-... 

Essential Oils Extraction of Oil of Cloves by Steam Distillation... 

Essential oils are volatile compounds responsible for the aromas commonly associated with many plants (see essay "Terpenes and Phenylpropanoids")- The chief constituent of the essential oil from cloves is aromatic and volatile with steam. In this experiment, you will isolate the main component derived from this spice by steam distillation. Steam distillation provides a means of isolating natural products, such as essential oils, without the risk of decomposing them thermally. Identification and characterization of this essential oil will be accomplished by infrared spectroscopy. 

Extraction of Essential Oils from Caraway, Cinnamon, Cloves, Cumin, Fennel, or Star Anise by Steam Distillation... 

In Experiment 54A, you will steam-distill the essential oil from a spice. You will choose, or the instructor will assign you, a spice from the following list caraway, cinnamon, cloves, cumin, fennel, or star anise. Each spice produces a relatively pure essential oil. The structures for the major essential oil components of the spices are shown here. Your spice will yield one of these compounds. You are to determine which structure represents the essential oil that was distilled from your spice. 

Essential Oils. Essential oils are generally obtained by steam distillation of plant materials (flowers, leaves, wood, bark, roots, seeds, and peel) and are used in perfumes, flavorings, cosmetics, soap, cleaning products, pharmaceuticals, and solvents. Examples include turpentine and oils of cloves, eucalyptus, lavender, and wintergreen. 

Essential (volatile) oils are obtained preferentially by steam distillation of plants (whole or parts) such as clove buds, nutmeg (mace), lemon, caraway, fennel, and cardamon fruits (cf. 22.1.1.1). After steam distillation, the essential oil is separated from the water layer, clarified and stored. The pressure and temperature used in the process are selected to incur the least possible loss of aroma substances by thermal decomposition, oxidation or hydrolysis. 

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