Filbertone

Blanch, G.P. and lauch, J. (1998) Enantiomeric composition of filbertone in hazelnuts in relation to extraction conditions. Multidimensional gas chromatography and gas chromatography mass spectrometry in the single ion monitoring mode of a natural sample. J. Agric. Food Chem., 46, 4283 1286. 

M. Glintert, R. Emberger, R. Hopp, M. Kbpsel, W. SUberzahn and P. Werkhoff. Chirospecific analysis in flavor and essential oil chemistry Part A. Filbertone - the character impact compound of hazel-nuts. Z. Lebensm. Unters. Forsch., 192. 108-110 (1991). 

Methyl-(E)-2-hepten-3-one (filbertone) has been identified as character impact odorant of roasted hazelnuts [90-92]. Its odour threshold is extremely low 5 ng/kg (water as solvent). 

Flores, G., Castillo, M.L.R., Herraiz, M., and Blanch, G.R Study of the adulteration of olive oil with hazelnut oil by on-line coupled high performance liquid chromatographic and gas chromatographic analysis of filbertone. Food Chemistry, 97(4), 742-749. 2006. 

Impact compound. The name for flavor compounds that decisively influence the character of an aroma or flavor, e.g., (-)- carvone in spearmint oil, citral in lemon oil, filbertone in filbert flavor, or vanillin in vanilla. For further examples, see literature. Lit. J.Food Sci.29, 158ff. (1964) Maarse.p. 237,292,456. 

Of special iirportance for the aroma of nougat is FUbertone, 5-methyl-(E)-2-hepten-3-one (odor threshold 5 ng/kg oil), which is produced during the roasting of hazelnuts. In a model experiment, the concentration of this compound increased at 180 °C from 1.4 to 660 pg/kg in 9 min and to 1150 pg/kg in 15min. In fact, 315pg/kg were found in a commercially produced oil from roasted nuts. Oil from unroasted nuts contains less than 10 pg/kg Filbertone. 

The presence of methylketones is undesirable in some fats, such as butter, coconut and pahn oil. Also undesirable are unsaturated ketones produced by oxidation of fatty acids, which are called alkyl vinyl ketones. For example, pent-l-en-3-one (8-47) smells of fish oil, oct-l-en-3-one (8-47) has a metallic taste, and (Z)-octa-l,5-dien-3-one (8-47) has an oily, greasy and metallic taste. A related ketone similarly formed by oxidation of fatty acids is (E)-5-methylhept-2-en-4-one (8-47), known as filbertone (Table 8.1), a key component of the odour of hazelnut and some chocolate products, such as nougat. Its content in raw nuts is low (about 1.4p,g/kg), but increases to 660p,g/kg in nuts roasted at 180 °C for 9 minutes, and to 1150p,g/kg in nuts roasted for 15 minutes. Hazelnuts contain a mixture of (-F)-(2E,5S)- and (-)-(2E,5R)-isomers (8-47). The enantiomeric composition of raw hazelnuts... 

The main (key) components of chocolate aroma are Cj carboxylic acids with a sweet smell (2-methylbutyric), lactones (y-lactone with a sweet, peachy aroma), aldehydes (such as isovaleraldehyde with a sharp odour resembling malt), ( )-non-2-enal (with green and tallowy smell), (2 ,4 )-nona-2,4-dienal and (2 ,4 )-deca-2,4-dienal (with oily smell resembling fried foods), ketones, such as oct-l-en-3-one (with the mushroom-like smell), (2 ,5S)- and (2 ,5 )-5-methyl-hept-2-en-4-one (known as filbertone, which has the odour of hazelnuts, 8-204), 2-ethyl-3,5-dimethylpyrazine (with a smell reminiscent of fried potato chips), 2-ethyl-3,6-dimethylpyrazine (with the smell of nuts with earthy tones) and methyl 2-methyl-3-furyl disulfide with meaty and sulfur smell. 

Ruiz Del Castillo M.L., Flores G., Herraiz M., Blanch G.P. Solid-phase microextraction for studies on the enantiomeric composition of filbertone in hazelnut oils. Journal of Agricultural and Food Chemistry, 51 2496-2500 (2003). 

The character impact compound of hazelnuts, ( )-5-methyl-2-hepten-4-one (filbertone), undergoes isomerization during the roasting process (62). Of the four possible geometric and enantiomeric isomers formed, all exhibit the typical... 

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