Peppermint

McjC = CHCOCH3. Colourless liquid b.p. 129"C, with a strong peppermint-like odour. Prepared by distilling diacetone alcohol in the presence of a trace of iodine. Converted to phorone by heating in propanone with dehydrating agents such as sulphuric acid. It is a solvent For cellulose acetate and ethyl-cellulose and other polymers. 

Piperitone is of considerable technical im portance. It is a colourless oil of a pleasant peppermint-like smell. (-)-Piperilone has b.p. 109-5-110-5 C/I5mm. Piperitone yields thymol on oxidation with FeCl. On reduction with hydrogen in presence of a nickel catalyst it yields menthone. On reduction with sodium in alcoholic solution all forms of piperitone yield racemic menthols and womenthols together with some racemic a-phel)andrene. 

Add cautiously 15 ml. of concentrated sulphuric acid to 50 ml. of water in a 100 ml. distilling-flask, and then add 10 g. of pinacol hydrate. Distil the solution slowly. When about 40 ml. of distillate (consisting of pinacolone and water) have been collected, and no more pinacolone comes over, extract the distillate with ether. Dry the extract over sodium sulphate. Distil the dry filtered extract carefully, with the normal precautions for ether distillation (p. 164). When the ether has been removed, continue the distillation slowly, rejecting any fraction coming over below 100 . Collect the pinacolone, b.p. 106 , as a colourless liquid having a peppermint odour. Yield, 4 5-5 o g. A small quantity of higher-boiling material remains in the flask. 

To counteraa chlorine or bromine fumes if inhaled in only small amounts, inhale ammonia vapour. Afterwards suck eucalyptus pastilles, or drink warm dilute peppermint or cinnamon essence, to soothe the throat and lungs. 

United States Exports of Spices and Oleoresins. The United States (ca 1993) is the foremost grower of peppermint, spearmint, orange, lemon, lime, and grapefmit products. The mints are processed to essential oils, and the citms fmit are sold as fresh fmit or processed to fro2en... 

Diisobutyl Ketone. Diisobutyl ketone (DIBK) (2,6-dimethyl-4-heptanone) is a colorless stable Hquid with a peppermint odor. Some physical properties are Hsted in Table 1. 

Whiffs of peppermint and lily of the valley improve the alertness of people engaged in monotonous tasks. 

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... 

In 1993, the United States imported nearly 22 x 10 kg of essential oils at a total value of almost 190 x 10 , an increase over 1992 of ca 2.3 X 10 kg and 935,000. Table 1 fists the quantities and values of 35 imported essential oils. The United States exports seven principal essential oils orange, lemon, peppermint, spearmint, cedarwood, clove, and nutmeg. The latter two are not grown in the United States but are imported as dried spice, processed for oil, and then exported. 

Menthol Manufacture. Of the menthol isomers, only (-)-menthol [2216-51 -5] and (+)-menthol [15356-70-4] are of commercial importance. The most important natural sources of (—)-menthol are the oUs of Mentha arvensis (75—90%) and Mentha piperita (50—65%). The main suppUers ate Japan, China, BrazU, and Taiwan for the former and the United States, CIS, Bulgaria, and Italy for the latter. (—)-Menthol is known for its refreshing, diffusive odor characteristic of peppermint. It also is known for its strong physiological cooling effect, which is useful in cigarettes, dentifrices, cosmetics, and pharmaceuticals. 

Natural menthol is obtained by freezing the essential oU, eg, Mentha arvensis and the menthol crystals ate separated by centrifuging the supernatant hquid away from the crystals. The supernatant oU is then caUed dementholized cornmint oU. Impurities in the crystals come from the essential oU and usuaUy give a slight peppermint aroma to the crystallized menthol. The cornmint oU, rich in (—)-menthone (- 28%) and (—)-menthol (- 32%), can be further processed to give additional natural menthol. 

Cyclohexanone [108-94-17 is a colorless, mobile Hquid with an odor suggestive of peppermint and acetone. Cyclohexanone is used chiefly as a chemical iatermediate and as a solvent for resias, lacquers, dyes, and iasecticides. Cyclohexanone was first prepared by the dry distillation of calcium pimelate [19455-79-9] OOC(CH2 )5COO Ca , and later by Bouveault by the catalytic dehydrogenation of cyclohexanol. 

Flavor. Dentifrices are used to refresh the oral cavity. Flavor oils and other flavoring materials are key to that function (see Flavors and spices). Generally recognized as safe (GRAS) flavors or flavors from approved lists are used. The most popular flavors are peppermint [8006-90-4], spearmint [8008-79-5], cinnamon [8006-79-9], and mixtures of these. Menthol is a principal constituent of the mint flavors and a source of refreshment and coolness. 

There is a senes of herbal drugs that are used on their own - they arc called mono- or monovalent drugs examples of these are chamomile flowers, peppermint leaves, wormwood, etc. This book described 181 such individual drugs. 

Parts Balm 10 Parts Peppermint leaves 25 Parts Valerian root 20 Parts Orange flowers 15 Parts Aniseed 20 Parts Passiflora... 

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