Analysis of tartary buckwheat (Fagopyrum tataricum) aroma compounds with GC-MS

Tartary buckwheat herb is an important functional food. Its grains have high nutritional value because of favourable amino acid composition, minerals, dietary fibre and a higher amount of flavonoids (rutin) than common buckwheat (Fagopyrum esculentum), but it is rarely consumed because of its bitter taste [1,2]. Aroma of tartary buckwheat significantly differs from that of common buckwheat in which salicylaldehyde was proven as the most characteristic component [3]. However, volatile aroma components of tartary buckwheat were not investigated so far. The aim of this work was identification and quantification of individual compounds responsible for aroma of tartary buckwheat. Volatiles from freshly ground buckwheat grains were extracted with distillation in Likens-Nickerson apparatus. The extracts were analysed by gas chromatography and mass spectrometry (GC-MS) with electron ionisation (EI). Compounds were identified on the basis of their EI spectra, and by comparison of their retention times with reference compounds. The compounds with significant contribution to the aroma (odour activity value, OAV >10) are mainly those with oxygen-containing functional groups like aldehydes ((E,E)-2,4-hexadienal, nonanal, (E)-2-nonenal, (E)-2-undecenal, phenylacetaldehyde), phenols (2-methoxy-4-vinylphenol), furan derivatives (2-pentylfuran) and sulphur compounds (isopropyl disulphide, 2-acetylthiazole), but no salicylaldehyde was found in the extracts.

References: 1. Fabjan, N. et al. (2003)J. Agric. Food Chem., 51:6452–6455.

2. Chia-Ling, L. et al.(2008)J. Agric. Food Chem., 56:173–178.

3. Janeš, D., Kreft, S. (2008). Food Chem. (109):293–298.