Enantiomeric composition of filbertone in hazelnuts and hazelnut oils from different geographical origins

Abstract

The potential of enantiomeric analysis of (E)-5-methyl-hept-2-en-4-one (filbertone) for authenticity control of oils is evaluated for a selection of both hazelnuts and hazelnut oils from different geographical origins. The analytical method proposed involves the enantioselective GC analysis of the fraction resulting from the preseparation with HPLC of either a hazelnut extract or a hazelnut oil. The obtained results demonstrate that the proposed procedure avoids the partial or total racemization of filbertone and thus allows the reliable determination of its enantiomeric composition. Moreover, the enantiomeric ratio of filbertone is not affected by the cold pressing process of hazelnut oil production and was found to be nearly constant for oils obtained from unroasted hazelnuts of different geographical origins.

Filbertone: A Review

“…Although the enantiomeric purity of filbertone 1A in samples obtained by SPME varies broadly in unroasted hazelnut oils (44–98% ee), in most cases, typical values between 70 and 90% ee were observed. Likewise, the enantiomeric composition of filbertone 1A in unroasted oils analyzed by techniques other than SPME ranged from 73 to 85% ee (with one exceptional case reporting only 43% ee) . As in the case of the fruits, significantly lower enantiomeric-excess values of filbertone 1A (14–43% ee) were observed when roasted nuts were used to obtain the hazelnut oil …”

“…For example, hazelnuts from Turkey contain ( S )- 1A with 54–56% ee, whereas those from Italy exhibit 62–63% ee. The highest enantiomeric excess of natural filbertone was reported in hazelnuts from California (70% ee) . Moreover, the enantiomeric purity of isolated filbertone is usually higher under mild extraction conditions.…”

“…The highest enantiomeric excess of natural filbertone was reported in hazelnuts from California (70% ee). 2 Moreover, the enantiomeric purity of isolated filbertone is usually higher under mild extraction conditions. There is also a remarkable difference between raw and roasted hazelnuts; 3 the enantiomeric excess of filbertone 1A drops from values of around 67% ee in raw hazelnuts to about 45% ee in roasted hazelnuts.…”

Ultrasonically assisted solid‐phase extraction and GC analysis of filbertone in hazelnut oil

“…Moreover, the comparison of the filbertone enantiomeric composition estimated from the latter hazelnut oil (i.e., about 20%) and from compositions in other oils (about 73%) (5) suggests that these differences may depend on whether the oil is obtained from roasted or unroasted hazelnuts. Also, it is evident that the exposure of the sample to some kind of heating (i.e., deodorization) could have promoted the loss of the analyzed compound and/or the modification of its enantiomeric distribution.…”

“…The absence or presence of filbertone also has been proposed to differentiate olive oil from hazelnut oil (3) and, thus, to detect adulterated samples (4). The interest in analyzing both R-and S-enantiomers of filbertone in a hazelnut oil has been underlined as a means to improve the reliability of filbertone detection as well as to investigate the natural compositional variability of filbertone in hazelnut oils (5).…”