Perfumes citrus oils

CH3(CH2)9CH0, C11H22O, Mr 170.29, bp2Ave 1°C, df 0.8251, ng 1.4325, occurs in citrus oils. It is a colorless liquid with a flowery-waxy odor that has aspects of freshness. Undecanal is the prototype of the perfumery aldehydes and is widely used in perfume compositions for imparting an aldehydic note. ... 

Otherwise, in general construction the perfume follows closely that of a classical oriental, with citrus oils (making up some 25%), lavender, sandalwood, patchouli, vanillin, coumarin, castoreum, and rose. The general sweetness of the perfume is further enhanced by the choice of musk materials, Galaxolide (5%), Tonalid, ethylene brassylate, and musk ketone, as well as by the use of Cashmeran, an intensely sweet fruity musk material associated with the synthesis of Galaxolide. 

The word "chypre derives from the island of Cyprus, which for many centuries was the meeting point between East and West for the trade in aromatic materials. During the nineteenth century it became famed for the production of perfumes combining the citrus oils, floral pomades, and labdanum of the Mediterranean region, with resins and gums, such as styrax, incense, opoponax, and myrrh, imported from Arabia. Animal products such as civet from Ethiopia and musk from the Himalayas were also among the most valued commodities. 

Note A classification of aromatic components of essential oils and perfumes. Top notes are sharp, penetrating and highly volatile (e.g. citrus oils, peppermint). Middle note characteristics are used to give body to blends (e.g. geranium, lavender). Base notes are the least volatile and used as fixatives to give more permanence (e.g. sandalwood, vetivert). 

The fractionation of citrus oil is an important subject in perfume industry. Citrus oil consists of terpenes (over 95 %), oxygenated compounds (less than 5 %), waxes, and pigments. Terpenes must be removed to stabilize the products and to dissolve it in aqueous solution. Terpenes are conventionally removed by distillation or solvent extraction, which involves higher temperature process resulting in thermal degradation of essential oil. Furthermore, nonvolatils such as waxes and pigments must be eliminated because of turbidity in the oil and phototoxic activity [1-2]. 

Usually, the terpenes are removed from the cold-pressed oils (deterpenation) to concentrate the flavour fraction, thus resulting in a more stable product with improved solubility in the alcoholic solvents used in food and perfume processing. Supercritical carbon dioxide extraction appears as a promising and alternative technique to refine cold-pressed citrus oils [1,2, 3). Potentially, it has the advantages that it can be carried out at mild temperatures, provides better yields and leaves no solvent residues. 

D-Limonene can be absorbed through the skin after application of citrus oils, perfumes, soaps, and other fragranced personal care products, and through skin contact with citrus-based cleaning products. 

While most perfumers employ raw citrus or petitgrain oils for usage in fragrance applications (solubility in alcoholic fragrances is sufficient and no thermal stress is required for fragrance applications), the usage of concentrated citrus oils is often called for in the food industry. Applications in beverages and foods require more sophisticated properties as far as solubility and stability are concerned. 

The epoxidation of terpenic substrates is of interest in the flavor and fragrance industry [55,56]. Terpenes are derivatives of isoprene, which has formula CsHg (2-methyl-frans-butadiene). There are tens of examples of terpenes, including limonene, a-pinene, geraniol, citronellol, myrcene, ocimene, camphene, a-terpin-eol, menthol, and isopugelol. Limonene is an abundant monoterpene extracted from citrus oil, which can be epoxidized to obtain fragrances, perfumes, and... 

While by definition, aroma compounds need to be volatile enough to be inhaled into the nose, flavor compounds can either be volatile or non-volatile. Volatile compounds typically have molecular weights below 300 Daltons. Nonvolatile flavor compounds can have molecular weights well over 300. Detection of non-volatiles requires the use of TLC or HPLC either alone or in tandem with an identification technique. HPLC-NMR can identify non-volatile coumarins, sterols, fatty acids and psoralens, in citrus oils, such as the substituted psoralen byakangelicol, found in lemon peel oil. Non-volatiles can act as odor fixatives, impacting the release of a perfume from the skin. Non-volatiles also serve as authentication markers that are difficult to adjust or circumvent (27). 

Use Mainly for the production of perfumes, especially Eau de Colognes and fresh toilet waters. Pressed B. contains up to ca. 1% of the furocoumarin bergap-ten which causes phototoxic reactions (so-called ber-lock or berloque (perfume) dermatitis). Thus mild rectification of B. is recommended before its use in perfume oils, since bergapten remains in the distillation residue. B. is also used in small amounts to aromatize confectionery and bakery products, often in combination with other citrus oils well known is the aromatization of tea ( Earl Grey tea). 

Use In the perfume industry, e.g., for fresh notes in Eaux de Cologne. However, on account of the content of furocoumarins (see also citrus oils) pressed L. is used in limited amounts only. Pressed L. is used to improve the aromatic character of foods similar to lemon oil and is usually employed in combination with lemon oil. 

One of the most prominent MT-hydrocarbons is (+)-limonene, which occurs in nearly every EO of the citrus oils and is a major compound (up to 97 % [11]) in sweet orange oil (from the peel of Citrus sinensis (L.) Osbeck, syn. Citrus aurantium var. sinensis). Its odor is reminiscent of the typical sweet orange flavor, whereas its antipode (-)-limonene possesses an odor that recalls turpentine [12]. Sweet orange oil achieves its main importance in the flavor and food industry because it is easily obtainable (yield 5 % [11]) and due to its pleasant odor, which is accepted by everyone and is caused by the character impact compound [13] (+)-limonene. In the past, the use of (+)-limonene has experienced a great expansion. Besides its use in the food industry, it is used as flavor and fragrance additive in cosmetics, soaps, and perfumes, and also in medicine to mask the bitter taste of... 

Some terms refer to fantasy perfumes, whose structures have become known as classic reference points, such as chypre, based on the contrast between ->bergamot and - oakmoss, or foug re, a bouquet built around - lavender, - vanilla and coumarine, or Eau de Cologne, a mixture of citrus oils, such as - lemon oil, - bergamot oil, - man-... 

Bergamot. Bergamot oil is produced by cold expression from peels of fmits from the small citms tree. Citrus bergamia. The fmits are inedible and of httle value. Bergamot is grown mainly in southern Italy and northern and western Africa. The oil is used to impart a sweet freshness to perfumes. Its largest chemical constituent, to the extent of 35—40%, is linalyl acetate [115-95-7] (1), with a much smaller amount of citral [5392-40-5] (2) as an important odor contributor. 

Essential oils are organic compounds derived from flowers, seeds, leaves, roots, resins, and citrus fruits. The structures of many fragrant compounds have been studied, and processes for making these valuable compounds in a laboratory have been developed. There are now approximately 5000 synthetically produced chemicals that are available to a perfumer. These chemicals include vanillin, rose oxides, and the damascenes, or rose ketones. 

The major components of elemi oil are limonene (40-72%), a-phellandrene (10-24%), and the sesquiterpene alcohol elemol (1-25%) [488-491]. Both the resinoid and the oil have a fresh, citrus-like, peppery odor and are used predominantly in soap perfumes. (FCT 1976 (14) p. 755 [8023-89-0] (oil), [9000-74-2] (resin). 

Cedrat. —The rind of the citron fruit—citrus medico, —yields the oil of cedrat, both by expression and distillation. Its odor is lemon-like. This oil is expensive, and is mixed" only with the finer perfumes. 

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. 

Figure 10.11 Comparison of the mass spectra of a neroli oil peak (camphene) obtained by HPLC-HRGC-MS (a) and GC-MS (b) with a library spectrum of the same compound (c). Reprinted from Perfumer and Flavorist, 21, L. Mondello et al., On-line HPLC-HRGC in the analytical chemistry of citrus essential oils , pp. 25-49, 1996, with permission from Allured Publishing Corp.

L. Mondello, G. Dugo, P. Dugo and K. Bartle, On-line HPLC-HRGC in the analytical chemistry of citrus essential oils , Perfumer Flavorist 21 25 -49 (1996). 

Most perfume compounds containing essential oils will deteriorate when exposed to the air, and a number of different reactions can be involved, all of which come under the general heading of oxidation, brought about by the presence of oxygen. Many of the unsaturated monoterpenes, which occur widely in citrus, coniferous, and seed oils,... 

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