TY - JOUR
T1 - Development of a stable isotope dilution assay for the quantification of 5-methyl-(E)-2-hepten-4-one
T2 - Application to hazelnut oils and hazelnuts
AU - Pfnuer, P.
AU - Matsui, T.
AU - Grosch, W.
AU - Guth, H.
AU - Hofmann, T.
AU - Schieberle, P.
PY - 1999/5
Y1 - 1999/5
N2 - A stable isotope dilution assay was developed for the quantitation of the hazelnut odorant 5-methyl-(E)-2-hepten-4-one by mass chromatography using synthesized [2H]2-5-methyl-(E)-2-hepten-4-one as the internal standard. Application of the method on two batches of commercial hazelnut oils, processed from either roasted or unroasted nuts, revealed 6.4 μg 5-methyl- (E)-2-hepten-4-one per kg of unroasted oil whereas 315.8 μg per kg was determined in the roasted nut oil. The about 50-fold higher amount of 5- methyl-(E)-2-hepten-4-one in roasted hazelnut oil suggested the necessity of a thermal treatment to generate the flavor compound. Pan frying of raw hazelnuts (9 to 15 min) or boiling of the crushed nut material for 1 h in water led to an increase of 5-methyl-(E)-2-hepten-4-one by factors of 600 and 800, respectively, thereby corroborating that the major part of the nut flavorant is formed during heat treatment from a yet unknown precursor in hazelnuts.
AB - A stable isotope dilution assay was developed for the quantitation of the hazelnut odorant 5-methyl-(E)-2-hepten-4-one by mass chromatography using synthesized [2H]2-5-methyl-(E)-2-hepten-4-one as the internal standard. Application of the method on two batches of commercial hazelnut oils, processed from either roasted or unroasted nuts, revealed 6.4 μg 5-methyl- (E)-2-hepten-4-one per kg of unroasted oil whereas 315.8 μg per kg was determined in the roasted nut oil. The about 50-fold higher amount of 5- methyl-(E)-2-hepten-4-one in roasted hazelnut oil suggested the necessity of a thermal treatment to generate the flavor compound. Pan frying of raw hazelnuts (9 to 15 min) or boiling of the crushed nut material for 1 h in water led to an increase of 5-methyl-(E)-2-hepten-4-one by factors of 600 and 800, respectively, thereby corroborating that the major part of the nut flavorant is formed during heat treatment from a yet unknown precursor in hazelnuts.
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U2 - 10.1021/jf9810214
DO - 10.1021/jf9810214
M3 - Article
C2 - 10552493
AN - SCOPUS:0032840419
VL - 47
SP - 2044
EP - 2047
JO - Journal of Agricultural and Food Chemistry
JF - Journal of Agricultural and Food Chemistry
SN - 0021-8561
IS - 5
ER -