Bergamot

C10H13O. B.p. 225-226"C. A terpenic alcohol and a constituent of neroli, petit-grain and bergamot, and of many other essential oils. Nerol has a blander smell than its isomer, geraniol, and is more valuable as a constituent of perfumes. 

Oil-free alkyds Oil from seeds Oil-in-water emulsion Oil laundering Oil length Oil mining Oil of anise Oil of bergamot Oil of eucalyptus Oil oflemon Oil of Olay Oil of Palma Christi Oil of turpentine Oil Orange Oil-pump Oil reclaiming Oil recovery... 

Rectified oils have been redistilled to improve a particular property or characteristic, such as flavor or aroma. Eor example, natural oil of peppermint is frequently rectified to remove dimethyl sulfide, which has a powerful and objectionable cooked vegetable note deleterious to the use of the oil in cmme de menthe Hqueurs. Distillation is also used to remove psoralens, which are harmful photosensitizing agents present in natural bergamot oil. Color may be removed, eg, from cassia oil, by vacuum steam distillation. A desirable component, such as 1,8-cineole (eucalyptol) 85% in eucalyptus oil, may be... 

Phototoxicity is negative for all oils except bergamot, expressed, for which it is severe. 

B. D. Mookherjee, "The Identification of Bihmctional Compounds ia Bergamot Oil," paper presented at the 158th National Meeting of theMmerican Chemical Society, Sept. 7—12, 1969, New York. 

Citrus Family. This is a popular fragrance group noted for its refreshing brisk quaUty. Lemon, lime, orange, and bergamot are important ingredients. These oils combine well with lavender and amber accords. 

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. 

Minor Varieties. Brick teas are prepared in the former Soviet Union and in parts of the People s RepubHc of China (82). These products are often cooked as a soup with butter or other fats. Flavorants such as jasmine flowers maybe added during processing. Oil of bergamot is used to prepare Ead Grey tea. 

Uses ndReactions. Linalool can be estetified to linalyl acetate by reaction with acetic anhydride. Linalyl acetate [115-95-7] has a floral-fmity odor, reminiscent of bergamot and lavender. The price of the acetate in 1995 was 14.30/kg (45). Linalool is subject to dehydration and to isomerization to nerol and geraniol during the esterification. However, if the acetic acid formed during the esterification is removed in a distillation column, the isomerization can be minimized and good yields of the acetate obtained (130). 

Determination of the enantiomeric ratio of linalol and linalyl acetate in bergamot oil... 

Mondello et al. (2, 20-23) have used a multidimensional gas chromatographic system based on the use of mechanical valves which were stable at high temperatures developed in their laboratory for the determination of the enantiomeric distribution of monoterpene hydrocarbons (/3-pinene, sabinene and limonene) and monoterpene alcohols (linalol, terpinen-4-ol and a-terpineol) of citrus oils (lemon, mandarin, lime and bergamot). Linalyl acetate was also studied in bergamot oil. The system consisted of two Shimadzu Model 17 gas chromatographs, a six-port two-position valve and a hot transfer line. The system made it possible to carry out fully... 

L. Mondello, A. Verzera, P. Previti, F. Crispo and G. Dugo, Multidimensional capillar y GC-GC for the analysis of real complex samples. Part V. Enantiomeric distribution of monoterpene hydrocarbons, monoterpene alcohols and linalyl acetate of bergamot (Citrus bergamia Risso et Poiteau) oils , 7. Agric. Food Chem. 46 4275-4282 (1998). 

Linalol is a tertiary alcohol of the formula Cj HjgO, which, with its acetic ester (and traces of other esters) forms the basis of the perfume,of bergamot and lavender oils. By dehydration linalol is converted into terpenes of which the principal are limonene and dipentene, and by esterification into its acetic ester. The examination of the essential oil at different periods of the development of the bergamot fruit has led Charabot and Laloue to the following conclusions. As the fruit matures the essential oil undergoes the following modifications —... 

The practical conclusion to he drawn from this is as follows Oil of bergamot having a value which increases accoi ding to the richness in ester, it will be profitable to gather the harvest at the period at which the fruit is fully ripe. 

Thus as in the case of oil of bergamot, esterification is accompanied by a decrease in. the total proportion of linalol and in the proportion of free acid. These facts prove that, here also, the esters originate by the direct action of the acids on the alcohols. Under these conditions, as the plant develops, part of the linalol is esterified whilst another portion is dehydrated. So that not only does the proportion of free alcohol, but also that of the total alcohol decroase. But as the esterification process is completed, which happens when the flower commences to-fade, the total alcohols increase at a fairly rapid rate. 

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