Raspberry ketone
Raspberry ketone is a natural phenolic compound that is the primary aroma compound of red raspberries. It is used in perfumery, in cosmetics, and as a food additive to impart a fruity odor. It is one of the most expensive natural flavor components used in the food industry. The natural compound can cost as much as $20,000 per kg.[3] In 1965, the Food and Drug Administration placed raspberry ketone on generally recognized as safe (GRAS) status.[4]
In plants, raspberry ketone is synthesized from coumaroyl-CoA.[5] Extraction of pure raspberry ketone is usually 1-4 mg per kg of raspberries.[3]
Since the natural abundance of raspberry ketone is very low, it is prepared industrially by a variety of methods from chemical intermediates.[6] One of the ways this can be done is through a crossed aldol-catalytic hydrogenation. In acetone and sodium hydroxide, 4-hydroxybenzaldehyde can form the α,β-unsaturated ketone. This then goes through catalytic hydrogenation to produce raspberry ketone. This method produces a 99% yield.[7]
When given to mice in high doses (up to 2% of food intake), raspberry ketone has been shown to prevent high-fat-diet-induced elevations in body weight.[8] This effect is reported to stem from the alteration of lipid metabolism, increasing norepinephrine-induced lipolysis. Although products containing this compound are marketed for weight loss, this effect has not been studied in humans.
Print this Page