Aroma components, naturally occurring

A number of other valuable aroma chemicals can be isolated from essential oils, eg, eugenol from clove leaf oil, which can also, on treatment with strong caustic, be isomerked to isoeugenol, which on further chemical treatment can be converted to vanillin (qv). Sometimes the naturally occurring component does not requke prior isolation or concentration, as in the case of cinnamaldehyde in cassia oil which, on dkect treatment of the oil by a retro-aldol reaction, yields natural ben2aldehyde (qv). This product is purified by physical means. 

Ohloff, G., Recent developments In the field of naturally-occurring aroma components. In Progress In the Chemistry of Organic Natural Products, 1978, Vol. 35, p. 431, (founded by L. Zechmelster) W. Herz, H. Grlseback, G. W. Kirby, Ed. Sprlnger-Verlag Wien - New York. 

R = CH3, C10H12O2, Mr 164.20, 101.3 kPa 232.6 °C, dg 1.0883, ng 1.5171, occurs in a number of essential oils and is a volatile aroma component of many fruits and alcoholic beverages. Phenethyl acetate is a colorless liquid with a fine rose scent and a secondary, sweet, honey note. It is used in perfumery as a modifier of phenethyl alcohol, e.g., in rose and lilac compositions. In addition, it is used in a large number of aromas, in keeping with its natural occurrence. 

The restricted space available for these Reports unfortunately does not allow the discussion of a number of topics of interest to monoterpenoid chemists useful reviews of such topics include monoterpenoid alkaloids/ carbazole alkaloids/ isoprenoids and alkaloids of tobacco/" naturally occurring plant coumarins/ the biosynthesis of aromatic hemiterpenes/ and recent developments in the field of naturally occurring aroma components/ The poor quality of the Chemical Abstracts makes it difficult to assess the significance of a number of reviews of potential industrial interest/ A volume in the Methodicum Chimicum series includes a very brief discussion of some monoterpenoids/"... 

Production Even today many aroma chemicals are still isolated from essential oils, others are prepared semisynthetically from the components of the oils or from other suitable oiganic compounds. The proportion of natural and nature identical aroma chemicals used in the perfume industry is ca. 70%. The aroma chemicals not occurring in nature are often structural analogues of natural products that are difficult to synthesize, e.g., the sandalwood aroma chemicals prepared from campholene aldehyde or camphene and guaiacol as substitutes for the expensive sandalwood oil or santalols. 

Contents 0. R. GOTTLIEB, Neolignans - K. HERRMANN, Hydroxy-zimtsauren und Hydroxybenzoesauren enthaltende Naturstoffe in Pflan-zen - G. PATTEN DEN, Natural 4-Ylidenebutenolides and 4-Ylidene-tetronic Acids - R. D. H. MURRAY, Naturally Occurring Plant Coumarins - G. OHLOFF, Recent Developments in the Field of Naturally-Occurring Aroma Components - Author Index - Subject Index. 

Har orne, J. B. Introduction to Ecological Biochemistry. Academic Press, New York 1982 Ohloff, G. Recent developments in the fields of naturally occurring aroma components. Prog. Chem. Org. Nat. Prod. 35, 431-527 (1978)... 

Lower molecular weight, naturally occurring esters make major contributions to the pleasant aromas of fruits and flowers. These odors have been shown to be composed generally of complex mixtures of materials that have been separated only since the development of modern chemical instrumentation. Single components, however, may play a dominant role... 

Nerolidol is a natural occurring aliphatic SQT-alcohol that possesses one chiral center in its structure it prevails as a mixture of its cis and trans-form. It is an isomer of famesol, from which it is distinguishable by a different position of one double bond and the hydroxyl-group. Nerolidol is a major component of EO extracted from many plants [50-52]. It has a woody aroma reminiscent of tree bark. It is used to enhance flavor and aroma and is also used as a fragrance in perfumes, cosmetics, shampoos, toilet soaps and, household products. [53]. 

Carvone, the main component of spearmint oil, is an oily liquid at room temperature. It occurs naturally in spearmint, caraway seed, dill seed, gingergrass, and mandarin peel. Because of its pleasant aroma and flavor, carvone is added to liqueurs, chewing gum, soaps, and perfumes. It is one of a number of naturally occurring essential oils that have been used as spices, perfumes, and medicines for thousands of years. 

Recent Developments in the Field of Naturally-Occurring Aroma Components... 

Recent Developments in the Field of Naturally-Occurring Aroma Components 435 Table 3. Threshold Values (T) in ppb of Water... 

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