Aroma Compounds in Buckwheat (Fagopyrum esculentum Moench) Groats, Flour, Bran, and Husk

Buckwheat is a pseudocereal with a strong characteristic aroma. Compounds responsible for the aroma of buckwheat groats were recently identified, but the distribution of aromatic compounds between different fractions of the buckwheat kernel (flour, bran, and husk) is not yet known. In this study, the composition of aromatic compounds in buckwheat seed fractions was investigated and compared to the composition of aromatic compounds in groats produced from the same batch of buckwheat seeds. Volatiles from each sample were extracted with simultaneous distillation/extraction with a Likens-Nickerson apparatus. Extracts were analyzed by gas chromatography coupled with mass spectrometry (GC-MS) with electron ionization. Apart from the aroma molecules present in all fractions, compounds that are present only in flour or bran, but not in groats, were also found. Furthermore, some compounds were identified only in buckwheat groats but not in buckwheat flour or bran [octanal, (E,E)-2,4-heptadienal, (E)-2-decenal, and (E,E)-2,4-decadienal], others were identified only in husks [(E)-2-hexenal, heptanal, (E,E)-2,4-hexadienal, phenylacetaldehyde, and alpha-bisabolol].