Filbertone: A Review

Abstract

This comprehensive review of filbertone, a principal flavor compound of hazelnut, evaluates the current state of the art of all relevant aspects of the title molecule: its occurrence and properties, laboratory preparation and bulk synthesis, analytical issues regarding stereochemistry and purity, sensory evaluation, and practical uses. Comparisons are made between different synthetic approaches, and a critical assessment of various applications is presented.

Filbertone Ameliorates Adiposity in Mice Fed a High-Fat Diet via Activation of cAMP Signaling

“…We recently undertook a phenotype-based screen in adipocytes for phytochemicals that could ameliorate intracellular lipid accumulation. In this screen, we found filbertone (C 8 H 14 O), a major flavor compound in the fruits of hazel trees ( Corylus avellana and Corylus maxima ) [12], to be a good candidate molecule warranting further investigation. Filbertone has been acknowledged as a commonly accepted safe chemical by the Flavor and Extract Manufacturers Association (FEMA) [13].…”

“…Filbertone has been acknowledged as a commonly accepted safe chemical by the Flavor and Extract Manufacturers Association (FEMA) [13]. Although this compound is widely used as a food flavoring in nuts, coffee, cocoa, meat, mints, and tropical, citrus, or fruity foods [12], research on the physiological roles of filbertone is limited. In the present study, we aimed to test whether filbertone protects against HFD-induced adiposity in mice, and, if so, to clarify whether filbertone exerts its anti-obesity effect via activation of the cAMP pathway.…”

Corylus avellana L. Aroma Blueprint: Potent Odorants Signatures in the Volatilome of High Quality Hazelnuts

“…The molecule configuration is crucial in determining its aroma perception: enantiomers may differ in the aroma intensity, as it is the case of menthol and camphor, or even in the flavor itself, as it is for 3-methylthiobutanal (i.e., methional) where the ( R )-configured molecule elicits the typical odor of cooked potatoes , while the (S)-configured stereoisomer is odorless (Weber and Mosandl, 1997 ; Zawirska-wojtasiak, 2006 ). Such characteristic is fundamental with hazelnuts too since filbertone (i.e., 5-methyl-( E )-2-hepten-4-one), the key-odorant contributing to the nutty aroma (Jauch et al, 1989 ; Alasalvar et al, 2004 ; Burdack-Freitag and Schieberle, 2012 ; Kiefl et al, 2013 ), might be present as R or S enantiomer(s) on the chiral center on C5 (Puchl'ová and Szolcsányi, 2018 ).…”

Corylus avellana L. Natural Signature: Chiral Recognition of Selected Informative Components in the Volatilome of High-Quality Hazelnuts

“…However, information is lacking concerning the enantiomeric recognition of many known aroma compounds. In this regard, the attention has been mainly focused on the enantiomeric characterization of the hazelnut’s key-odorant, ( E )-5-methyl-2-hepten-4-one (i.e., filbertone), and of its geometrical isomer, ( Z )-5-methyl-2-hepten-4-one, since the four diastereoisomers are characterized by different sensory properties ( Güntert et al, 1991 ; Puchl’ová and Szolcsányi, 2018 ). Güntert et al (1991) performed a full assessment and olfactory comparison of all four possible stereoisomers showing that the (+)-(5 S )-( E )-5-methyl-2-hepten-4-one has hazelnut , fatty , metallic , balsamic notes, the (-)-(5 R )-( E )- and (-)-(5 R )-( Z )-isomers show hazelnut and woody odors, and the (+)-(5 S )-( Z )-5-methyl-2-hepten-4-one has hazelnut , woody, fatty, metallic notes.…”

“…Naturally occurring filbertone in hazelnuts exhibits low-to-medium enantiomeric excess, with a higher amount of (S) -enantiomer compared to the opposite enantiomer. The ratio between the two enantiomers is variable and depends on the origin of the hazelnuts, thermal treatment, analytical sample collection, and technological processing ( Jauch et al, 1989 ; Güntert et al, 1991 ; Puchl’ová and Szolcsányi, 2018 ). There is also a remarkable difference between the enantiomeric excess of raw and roasted hazelnuts since, although the absolute amount of filbertone increases about 10-fold in roasted hazelnut compared to raw hazelnut ( Pfnuer et al, 1999 ), the relative difference between the two enantiomers drop-down to lower enantiomeric excess for the (S) -filbertone ( Güntert et al, 1991 ; Blanch and Jauch, 1998 ; Puchl’ová and Szolcsányi, 2018 ).…”