Flavors raspberry ketone

Hydroxybenzaldehyde has an agreeable aromatic odor, but is not itself a fragrance. It is, however, a useful intermediate in the synthesis of fragrances. The methyl ether of -hydroxybenzaldehyde, ie, -anisaldehyde, is a commercially important fragrance. Anisaldehyde can be made in a simple one-step synthesis from hydroxybenzaldehyde and methyl chloride. Another important fragrance, 4-(p-hydroxyphenyl)butanone, commonly referred to as raspberry ketone, can be prepared from the reaction of -hydroxybenzaldehyde and acetone, followed by reduction (see Flavors and spices). 

Raspberry ketone, a popular flavor and fragrance chemical, used as food additive may be made from p-cre-sol through its oxidation product p-hydroxy benzaldehyde. 

Raspberry flavor More than 250 flavor compounds are currently known. The aroma is mainly due to the impact compound 4-(4-hydroxyphenyl)-2-butanone (so-called raspberry ketone, see zingerone) in combination with a- and jS- ionones. Additional contribu-... 

ChHhOj, Mr 194.23, hot-tasting crystals, mp. 40°C, bp. 187 -188 °C (1.9 kPa). Z. is the pungent (hot) flavor principle in the oleoresin of ginger. 4-(4-hydroxy-phenyl)-2-butanone rheosmin, raspberry ketone, frambinone), CioHuOj, Mr 164.20, needles, mp. 82 C, is a component of raspberry flavor. It acts as a kairo-mone on the melon fly Dacus cucurbitae and related species. It is used as a flavor substance. 

The precursors of some phenylpropanoid odor/flavor components of raspberry fruit occur as the 4 -0-p-D-gluco-pyranoside of 4-(4 -hydroxyphenyl)butan-2-one (raspberry ketone) and the S -O-p-o-glucopyranoside of 4-(3, 4 -dihy-droxyphenyl)butan-2-one (Pabst et al., 1990). 

Compound 68a is reduced to the allylic alcohol 71a of (5) absolute configuration with no trace of the saturated species 69a and 70a. In contrast, the unsaturated ketone 68b is transformed almost completely into the saturated ketone 69b before any saturated alcohol 70b appears in the mixture. This result is of interest in that it allows the selective production of the saturated ketone 69b, the impact flavor of raspberries. Starting with 68b of natural origin, the biotransformation allows one to obtain natural raspberry ketone 69b. The reduction occurs using yeast enzyme concentrate (Sigma type II) in the presence of NADPH or NADH. When 4K)- and (4S)-[4-2H]-NADPH or NADH were used, the experiments showed that both cofactors were utilized but with opposite stereochemistry, thus suggesting the presence of two different enone reductases. 

Few of the phenol derivatives that have a keto substituent in their side-chain are of interest as fragrance or flavor substances. A number of phenols and phenyl ethers acetylated in the benzene ring have been identified as volatile components of foods. 4-Methoxyacetophenone is of some interest as a fragrance material. 4-Hydroxybenzylacetone, a higher mass phenol ketone, has a characteristic raspberry aroma. 

The ketone is used in fruit flavors, particularly in raspberry compositions. 

Acetone is the major component of fingernail polish remover. Like aldehydes, ketones are found in several natural flavors and aromas. 2-Heptanone adds to the pleasant smell of cloves, lonone is the molecule you smell when picking and eating raspberries. 

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